Original report follows:

Reports that Solidigm was considering building a 3D NAND fab in the U.S. came as a surprise last month, as no company has manufactured NAND flash memory in America for years. However, the potential investment now appears to be part of a calculated move by Solidigm's parent, SK hynix, which is reportedly asking the U.S. government to authorize additional semiconductor manufacturing equipment shipments to its Dalian facility in China in exchange for a commitment to build a new NAND fab in the U.S., according to Reuters.

The Dalian fab is the world's only facility to produce 192-layer floating gate 3D NAND for Solidigm's data center-grade SSDs for AI, enterprise, and hyperscale data centers. Its manufacturing operations rely on equipment from major American suppliers, including Applied Materials, KLA, and Lam Research, whose exports to China require a license from the U.S. government. Although the U.S. authorities tend to authorize shipments of some tools to semiconductor facilities in the People's Republic that are operated by multinational companies like Samsung or SK hynix, they only want to keep the fabs running, as they are against expansions of capacity of fabs in China or introducing new manufacturing technologies to these facilities.

Solidigm has requested U.S. export licenses for additional tools, but the U.S. government has yet to authorize the shipments. Last December, the U.S. Commerce Department granted SK hynix a limited authorization for equipment deliveries to Dalian for 2026, but it has not issued a similar equipment export authorization for 2027, according to Reuters. In a bid to persuade the U.S. government to authorize shipments of necessary tools to its Dalian facility, SK hynix proposes to build a 3D NAND facility in America. This would fill an important gap in the Trump administration’s efforts to bring semiconductor manufacturing back to the U.S.

SK hynix's Solidigm subsidiary wants to install additional manufacturing equipment in the unused portions of its Dalian Mod B facility, which was completed in 2023. The company never fully equipped the building because of the memory market downturn at the time, so while some production tools are installed, substantial space remains unused and is available for additional tools. Given that Solidigm sells every single SSD it produces, unused capacity means lost revenue. Meanwhile, because the building was completed in 2023, installation of tools into that facility does not constitute a capacity expansion.

Additional NAND production in China could generate profits that Solidigm could use to finance its proposed American fab and support its operations until domestic manufacturing capacity becomes available. The company is also considering an initial public offering as early as 2027 to raise additional capital.

Solidigm has previously confirmed its commitment to further development of floating-gate 3D NAND technology. In an interview with Tom's Hardware at Computex 2026, Avi Shetty, who leads Solidigm's AI solutions and ecosystem business, said that the company intended to develop 5^th and 6^th Generation floating-gate NAND beyond its existing 192-layer technology. He also emphasized the importance of maximizing factory utilization and profitability. However, he did not disclose plans to expand manufacturing output at the company's Dalian facility, not to mention a new fab in the U.S.

Nonetheless, the new reports about SK hynix's intentions clearly indicate that the company not only intends to keep developing new generations of Solidigm's floating-gate NAND, but also to expand its production in China and the U.S.

SK hynix has detailed plans to reduce reliance on power-hungry CPU cores with an in-house core named a Hynix Transaction Processing Unit (H-TPU). Not to be confused with an AI accelerator, an H-TPU would assist with repetitive work handled by an SSD, which usually demands more cores on a controller as drives get faster. These new cores are placed in clusters and would handle routine I/O with a four-stage, in-order pipeline, while management is left to the traditional Arm CPU. The new, tiny cores are claimed to draw only about 2.5% of a general-purpose CPU core’s power, with just around 4% of its area. Now, the company plans to apply H-TPU across its portfolio of products, TheElec reports.

The company’s VP of system-on-chip (SoC) design, Koo In-jae, spoke at ISOCC 2026, the International SoC Design Conference, earlier this week, saying that SSD controller CPUs are at their limit on power and area. In the talk, titled “From SSD Controllers to AI Memory SoCs,” he said that PCIe bandwidth doubles every generation, and controller CPU clocks and control capability reportedly can’t keep up. SK hynix reportedly plans to apply H-TPU across its NAND products, including next-gen enterprise SSD controllers. That’s where the unending chase for IOPS makes the problem most evident.

Koo’s comments underline the issue of scaling, which is evident in the “more cores” solutions found in competitor products. Marvell’s PCIe 6.0 Bravera SC6 uses 12 Cortex-R82 cores in two six-core clusters with three Cortex-M7 cores and a secure Cortex-M3. Compare this to its PCIe 5.0 predecessor, the Bravera SC5, which lists 10 Cortex-R8 and Cortex-M7 cores plus a Cortex-M3 for security. Core counts have climbed with PCIe speeds out of necessity.

SK hynix’s answer is a core of its own design: the H-TPU, kept small and programmable. It comes with a dedicated compiler and other development tools for specialized code. It’s stated to use a four-stage pipeline with in-order, or sequential, execution. It is not superscalar, does not use out-of-order units, and should not be confused with a tensor processor for AI. It is designed to handle read and write command processing, manage metadata, and handle buffer control, all repetitive tasks.

Storage control requires more than 100 detailed functions, which is not ideal for a monolithic CPU. Instead, SK hynix broke those functions up and spread them across “dozens of small TPU clusters,” according to ZDNet Korea (translated). Each H-TPU therefore has a specialized job. The total number of H-TPUs is more than 100; the function count above is a separate figure. However we currently have no details on how many cores each cluster holds.

The main CPU still handles error recovery and exception handling, plus storage-policy management, so the H-TPU complements the CPU: offloading, not replacement. The design idles the cores a given I/O doesn’t need, which reportedly drop into a minimum-power mode. Neither report names the CPU core behind SK hynix’s 2.5% power and 4% area figures.

Splitting the workload this way is not a new idea. Phison’s CoXProcessor, which pairs Cortex-R5 cores with hardened macros to offload repetitive firmware at wire speed, has been in products for some time. The company’s E18 SSD controller uses two lower-clocked Cortex-R5 cores to supplement the three main ones. On the enterprise side, Phison’s X1 used two Cortex-R5 cores plus up to 32 “micro cores,” each dedicated to one or two tasks. H-TPU takes this approach to a larger scale.

While the talk itself is light on detail, we discovered multiple SK hynix patents that describe a similar split between small cores and a CPU. U.S. patent 11,675,537, first filed in Korea in November 2020, details a CPU-run control plane and an I/O plane of many small processors, sorted into four groups by job. A command passes through all four in order: host for ingestion, cache, map, and NVM to the NAND. The processors “configure a pipeline for the data I/O operation” this way, letting the CPU handle any exceptions. That pipeline runs across many cores and is unrelated to the four-stage pipeline inside each H-TPU.

In the patent’s example, each small core is around “200,000 logic gates” rather than the “seven million logic gates” of the CPU, or about 2.9% of the CPU’s gate count. These are not fixed elements, as “firmware may be driven in each of the TPUs,” making them more adaptable than the hardware circuits the patent calls “difficult to modify.” The patent spells out TPU as “Tensor Processing Units,” but, again, this should not be confused with AI accelerators. H-TPU shares that programmable approach, but the next step SK hynix described moves some routine jobs into fixed hardware.

This next step is hardware automation (HWA), with command processing, address lookup, and buffer copies moved to dedicated circuits. The CPU and H-TPUs still handle exceptions and key policy decisions. Moving to this framework is meant to keep completion times predictable, which is necessary with I/O, especially for today’s high-IOPS enterprise SSDs.

SK hynix has filed on fixed-hardware paths before, with a 2014 filing by its San Jose-based unit and, later, with U.S. patent 12,216,914, first filed in Korea in 2022. The latter describes a “write automation circuit” and says “a task without intelligent control can be handled or processed through the hardware layer,” while firmware keeps jobs such as garbage collection. The former went further, sending basic I/O commands down a path “completely implemented in hardware,” with anything it couldn’t handle being sent upstream.

The H-TPU itself is reportedly being used in “Storage Next,” Nvidia’s name for the joint AIN P project with SK hynix. Storage Next targets 512-byte or more limited access with NAND, which traditionally aims at higher operating sizes. SK hynix also plans to apply it to high-bandwidth flash (HBF), which the outlet said is due next year. HBF stacks NAND dies for AI inference, targeting high-bandwidth memory (HBM) levels of bandwidth but with far more capacity, with up to 512GB per stack versus 64GB for HBM4.

For HBF, AI inference reads outnumber writes around 300,000 to 1, with the AI compiler and runtime passing pre-analyzed dataflow to the HBF SoC. Proper buffer management and prefetching based on that dataflow are meant to hide the slow NAND latency behind compute. Size is important in HBF stacks, so a traditional multi-core Arm design is likely less practical.

H-TPU has yet to be proven in an actual enterprise SSD controller product, and no date has been given. The move from general-purpose CPU cores to specialized single-job cores and circuits matches the type of workload SSDs handle, and the demands on storage are only increasing as AI servers become memory-constrained.

SK hynix’s statements and patents support an evolution to H-TPU and beyond to HWA, with H-TPU itself headed for traditional NAND and next year’s HBF. SSD controller manufacturers must be willing to adapt, as simple scaling is suboptimal even at current PCIe levels, let alone the speeds promised for PCIe 7.0 and 8.0, the latter headed for final ratification in 2028.

Sandisk is back with another welcome SSD, the NAS 800. As the name implies, this drive is designed for NAS appliances, but could also be a good choice for high-end desktop and enthusiast workstations. We recently reviewed the Optimus GX Pro 850P, a consumer drive for the PS5, so SanDisk is on a roll. The company has made it clear it wants to support the broader consumer market, as it’s even bringing back SATA SSDs in the form of the 320 and 520 series. The NAS 800 is closer in theme to the WD Red series of drives, like the WD Red SN700, which are optimized for home and small-business servers.

At its heart, the NAS 800 is a specialized, optimized Sandisk Optimus GX Pro 8100 (formerly the WD Black SN8100). That progenitor is one of the best drives on the market. It has a stellar controller and excellent all-around flash with good power efficiency and low latency. This makes a great base for a NAS drive, although some changes are necessary. The bones are good, though, and this drive could be used in any system. The only real issue is that you’re paying a premium for the NAS optimizations, and that’s where our focus is.

Sandisk NAS 800 Specifications

The Sandisk NAS 800 has some strange capacities, at least compared to consumer offerings, because the drives reserve more spare flash as overprovisioning, which improves endurance. The drive comes in 960GB, 1.92TB, 3.84TB, and 7.68TB flavors. The final one is the most welcome, as it’s been difficult to find larger drives outside of enterprise. Performance is excellent, at up to 14,900 / 13,200 MB/s for sequential reads and writes and up to 2,300K / 2,100K random read and write IOPS. Peak overall performance should be achieved at 3.84TB.

Write endurance is where this drive really stands out. It’s rated for up to 14PBW at its maximum capacity. Proportional to size, this puts it at almost three times the normal for consumer drives. The drive also supports TCG Opal self-encryption for data at rest, as would be expected for a drive in this class. Things are capped off with a standard five-year warranty.

You pay for this performance and endurance. At the time of writing,SanDisk’ss store lists the four capacities at $387.99, $699.99, $1,374.99, and $2,749.99. That’s roughly 45% to 65% more than the WD Black SN8100’s current street prices. Against the same drive under its new Optimus GX Pro 8100 name, the premium is between 27% and 29% at the time of review. The extra cost comes partly from the drive’s optimization but mostly from its TBW rating. You’re getting about one drive write per day over the five-year warranty, which is all but required for a drive of this type, and worthy of the price tag if you’re focused on endurance.

Sandisk NAS 800 Software and Accessories

If you own a Sandisk drive, or a WD drive for that matter, then you should be no stranger to the NAS 800’s software offerings. Sandisk has its own dashboard, aptly named Sandisk Dashboard, which follows the popular WD Dashboard. This SSD toolbox has all the information you need for your drive, including important SMART and health information. It also lets you enable optional features, find firmware updates, and more. Sandisk also provides a download for its OEM version of Acronis True Image, useful for backing up your files or cloning your drive.

Sandisk NAS 800: A Closer Look

The 1,920GB, or 1.92TB, version of the NAS 800 is single-sided. That also applies to the 960GB and 3.84TB versions. Only the 7.68TB version is double-sided, although that shouldn’t generally preclude you from using it in devices that would benefit from the drive. It could make a difference for certain cooling arrangements. The drive’s rating of 3.3V / 2.7A puts it at around 9W, which is between the drive’s maximum power state of 9.50W and its 6.5W / 6.4W average draw for this capacity. The reported active draw of 7.52W is higher than this average, but given that this drive is NAS-optimized with a small pseudo-SLC (pSLC) cache, it will likely be lower in practice. The drive should run cooler as a result.

The drive layout includes the SSD controller, a DRAM package, and two NAND flash packages. The 7.68TB version will need more packages on the rear, for a total of four flash packages. The controller is labeled in a way similar to SanDisk’s proprietary parts, but the “250800” spells out that this is a Silicon Motion, or SMI, SM2508. This is an eight-channel, high-end PCIe 5.0 SSD controller with generally excellent performance and power efficiency.

The DRAM package is LPDDR4 and is therefore a more power-efficient choice. It’s also 2GB, which follows the normal 1:1,000 ratio of DRAM to NAND. Our recent Optimus GX Pro 850P review had a 2TB drive from Sandisk with only 1GB of RAM. That’s perfectly suitable for gaming use. For this NAS drive, 2GB is very much preferred. The controller and DRAM are paired with SanDisk’s 218-layer BiCS8 TLC flash. This is some of the best flash on the market, with good all-around performance, very good latency, and very good power efficiency. This is world-class hardware, and the price reflects that.

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Comparison Products

The Sandisk NAS 800 technically has little competition in this market. We do have the Gen 4 Addlink NAS D60 with power-loss protection, but it’s otherwise pretty thin, particularly for Gen 5. The closest non-NAS retail drive in Gen 4 is the WD Black SN850X. For Gen 5, we have the WD Black SN8100, which has the same hardware as the NAS 800, and the same goes for the Kingston Fury Renegade G5. The Crucial T710 and Lexar NM1090 Pro use the same controller but two different generations of Micron flash rather than Kioxia or Sandisk flash. Phison is represented by the Corsair MP700 Pro XT, while the main proprietary option here is Samsung’s 9100 Pro.

Trace Testing — 3DMark Storage Benchmark

Built for gamers, 3DMark’s Storage Benchmark focuses on real-world gaming performance. Each round in this benchmark stresses storage based on gaming activities including loading games, saving progress, installing game files, and recording gameplay video streams. Future gaming benchmarks will be DirectStorage-inclusive and an evaluation for future-proofing is included where applicable.

We wouldn’t normally recommend a NAS drive for gaming, but if you happen to use this drive, you would be good to go. The NAS 800’s flash is known for being low-latency, and while it doesn’t perform up to the Black SN8100’s level, it’s in the same ballpark as the T710 and 9100 Pro. The drive does not seem optimized for it, though, as it does lose quite a bit of performance against the Black SN8100, which has the same hardware. This is still more than fast enough for games. You would be plenty happy with just the Black SN850X.

Trace Testing — PCMark 10 Storage Benchmark

PCMark 10 is an industry standard trace-based benchmark that uses a wide-ranging set of real-world traces from popular applications and everyday tasks to measure the performance of storage devices. The results are particularly useful when analyzing drives for their use as primary/boot storage devices and in work environments.

Performance is a bit weaker in PCMark 10 than in 3DMark. The NAS 800 finishes closer to the Lexar NM1090 Pro, which is not a bad drive but also not fully within the same class. We would expect it to be closer to the T710 and 9100 Pro. The Black SN8100 doesn’t shine quite as much here, either, but the NAS 800 trails it by 26%, a wider gap than the 21% in 3DMark.

This points to firmware tuning and other optimizations on the NAS 800, rather than a limitation of the shared hardware. The Phison-based MP700 Pro XT leads the pack and seems better optimized for PCMark. The NAS 800’s performance is still excellent in the grand scheme of things, though, well above Gen 4 drives. It’s just not our first choice for applications.

Console Testing — PlayStation 5 Transfers

The PlayStation 5 is capable of taking one additional PCIe 4.0 or faster SSD for extra game storage. While any 4.0 drive will technically work, Sony recommends drives that can deliver at least 5,500 MB/s of sequential read bandwidth for optimal performance. Based on our extensive testing, PCIe 5.0 SSDs don’t bring much to the table and generally shouldn’t be used in the PS5, especially as they may require additional cooling. Check our Best PS5 SSDs article for more information.

Our testing utilizes the PS5’s internal storage test and manual read/write tests with over 192GB of data both from and to the internal storage. Throttling is prevented where possible to see how each drive operates under ideal conditions. While game load times should not deviate much from drive to drive, our results can indicate which drives may be more responsive in long-term use.

If the NAS 800 is overkill for PC gaming, it’s really overkill for PS5 gaming. Performance is pretty good, as expected, but you’re leaving a lot of its bandwidth potential on the table. The drive is also not optimized for this type of workload. However, it could work if you do a lot of writes on your PS5 and want something with extreme endurance.

Transfer Rates — DiskBench

We use the DiskBench storage benchmarking tool to test file transfer performance with a custom 50GB dataset. We write 31,227 files of various types, such as pictures, PDFs, and videos to the test drive, then make a copy of that data to a new folder, and follow up with a reading test of a newly written 6.5GB zip file. This is a real-world type workload that fits into the cache of most drives.

At a quick glance, the NAS 800 does well with reads but not so well with writes and copying in our DiskBench test. Obviously, having slower writes will impact copy performance. That’s the reason the drive lags here, as the test works against the NAS 800’s design. Its roughly 12GB pSLC cache can only absorb the first quarter of the 50GB write, with the rest going straight to TLC. For that reason, its write score lands about 20% below the other Gen 5 drives, with a drop of 36% for copying against the same-hardware SN8100.

Admittedly, a NAS drive should be able to tackle file copying like this. A better test to show its value would be an extremely large transfer, where its steady-state performance would win out. Also, for smaller transfers, particularly random writes, its small cache would perform well. Know your workload before picking your drive.

Synthetic Testing — ATTO / CrystalDiskMark

ATTO and CrystalDiskMark (CDM) are free and easy-to-use storage benchmarking tools that SSD vendors commonly use to assign performance specifications to their products. Both of these tools give us insight into how each device handles different file sizes and at different queue depths for both sequential and random workloads.

The NAS 800 does quite well in ATTO and CDM where it matters. Its performance in ATTO is as expected, tracking the curve of the similar Black SN8100, and quite good on the whole. Write performance in particular is consistent.

In CDM, the drive is top in random read latency and nearly the top in random write latency. These are great numbers, and the drive is exceptionally responsive with 4KB low-queue-depth operations. Sequential performance is rougher but not terrible. Once queue depth gets up there (QD8), sequential read performance is effectively identical to the very fastest drives available. Sequential write performance is weaker, although we expect that to some degree on a drive optimized more for sustained writes. For internal transfers between very fast drives, this can be a factor, but the extra write endurance is a solid trade-off.

Sustained Write Performance and Cache Recovery

Official write specifications are only part of the performance picture. Most SSDs implement a write cache, which is a fast area of pseudo-SLC (single-bit) programmed flash that absorbs incoming data. Sustained write speeds can suffer tremendously once the workload spills outside of the cache and into the "native" TLC (three-bit) or QLC (four-bit) flash. Performance can suffer even more if the drive is forced to fold, the process of migrating data out of the cache in order to free up space for further incoming data.

We use Iometer to hammer the SSD with sequential writes for 15 minutes to measure both the size of the write cache and performance after the cache is saturated. We also monitor cache recovery via multiple idle rounds. This process shows the performance of the drive in various states including the steady state write performance.

The NAS 800 writes a bit differently than most other drives we’ve tested. It’s only pushing 12 GB/s for about a second in the pSLC mode, and then it drops to just below 4 GB/s for the direct-to-TLC mode. This indicates that the cache is likely static, that is, always available and in a usually high-endurance region. We’ve tested consumer drives with this setup in the past, like the original WD Black and the WD Black SN750. These drives were actually great for NAS. However, over time, it became clear that consumer workloads are bursty and prefer large, dynamic caches. Sandisk and Samsung use hybrid caches these days for the best of both worlds.

While small, a static cache can be useful for higher endurance, and it still handles many random writes just fine. As the cache comes from the base flash, its size is limited. The NAS 800 already has extra overprovisioning to increase its endurance, just as many enterprise drives have, which potentially limits the size of this cache even more. Typically, you would have about 24GB of static cache for 2TB and about 12GB for 1TB, give or take, so our guess is Sandisk is balancing all of this for endurance with the extra overprovisioning.

We find this to be a good trade-off, as 12GB is still quite a lot if you’re juggling smaller random writes. Those get handled by the pSLC cache, which likely has very high endurance, and then they are combined for low write amplification to the native TLC flash, or discarded if the writes aren’t kept. The static cache and native flash may have separate wear zones, which, in summary, means the cache arrangement can help support higher overall drive endurance.

Another big bonus of the small cache is that post-cache performance is high and consistent. At about 4 GB/s, it’s very fast for consumer-grade hardware, and this drive held that pace for a full hour in our testing. That’s a big selling point, and 4 GB/s is more than enough for 10GbE links. Internally, this can keep up with pretty much any Gen 4 drive in the long term. If arranged in an array, this level of performance is high enough for workstation and even some enterprise-level workloads. The T710 and MP700 Pro XT look faster on paper but are not as consistent.

Power Consumption and Temperature

We use the Quarch HD Programmable Power Module to gain a deeper understanding of power characteristics. Idle power consumption is an important aspect to consider, especially if you're looking for a laptop upgrade as even the best ultrabooks can have mediocre stock storage in terms of capacity and performance. Desktops are often more performance-oriented with less support for power-saving features so we show the worst-case for idle.

Some SSDs can consume watts of power at idle while better-suited ones sip just milliwatts. Average workload power consumption and max consumption are two other aspects of power consumption but performance-per-watt, or efficiency, is more important. A drive might consume more power during any given workload but accomplishing a task faster allows the drive to drop into an idle state more quickly, ultimately saving energy.

For temperature recording we currently poll the drive’s primary composite sensor during testing with a ~22°C ambient. Our testing is rigorous enough to heat the drive to a realistic ceiling temperature but real-world temperatures will vary due to the environment and workload factors.

The NAS 800 is not terribly efficient by Gen 5 standards, or even Gen 4, coming in under the Black SN850X. This is OK and explained by the fact that the drive has a very small pSLC cache. TLC flash is not as performant, so it does less work. Less power is used, but multi-bit programming is less efficient. When placed next to the D60, it becomes clear that the NAS 800’s results aren’t so bad, although the D60 has power-loss protection hardware, which can affect power consumption.

As we said, TLC can mean less power, so this lower level of efficiency does not translate to higher heat production. The drive hit a peak reading below 70 degrees Celsius in our testing, and as the drive is optimized for sustained writes, our type of testing is more relevant than usual. The drive has about 15 degrees of headroom if this reading correlates to the throttling temperature, which is acceptable to us, although certainly a heatsink is not unwelcome.

Test Bench and Testing Notes

We use an Alder Lake platform with most background applications such as indexing, Windows updates, and antivirus disabled in the OS to reduce run-to-run variability. Each SSD is prefilled to 50% capacity and tested as a secondary device. Unless noted, we use active cooling for all SSDs.

Sandisk NAS 800 Bottom Line

The Sandisk NAS 800 is not a drive for everyone. It’s priced too high for that, and its performance distinctly prefers certain workloads. Due to its optimization, it’s also not very power-efficient, so you might not want this in your laptop, either. This is all OK, though, because this drive is great at what it’s made for: NAS workloads.

Its sustained write performance, in particular, is high and consistent. It can also handle all of those writes with its exceptionally high TBW. The base hardware is fantastic in its own right, and there remain hints of that with the drive’s top-tier 4KB QD1 latencies, too. If you have a place for this drive and can afford it, it’s the best retail option out there for NAS.

There are some things the NAS 800 can’t do, though. It lacks power-loss protection hardware, like an array of capacitors. The D60 has these, and it’s one of the few retail options avialable with that feature. The NAS 800 is also not an ultra-low-latency option on par with a pSLC drive, or one with extreme endurance like the PNY LX3030, but that’s moot with no real products like that currently on the market.

We would instead look at two other possibilities: One, you go with a Gen 4 drive, or two, you grab an equivalent Gen 5 drive with a standard caching scheme. One downside for either is that you’re not getting the NAS 800’s high TBW. We also think the caching scheme works well for write-heavy workloads. Performance-wise, a Gen 4 drive could work as an alternative for many NAS applications, but we would highlight the NAS 800’s excellent latency as a counterpoint. If you need bandwidth, then there is not much of a substitute, either.

On the power-efficiency front, the NAS 800’s results are underwhelming, but expected. It would be wrong to take our numbers at face value for a drive that writes mostly in TLC mode. It’s plenty efficient for its intended workload, and the drive did not overheat in our testing.

As such, our biggest gripe is the price. We know what this hardware is, and we can account for the firmware optimization and the pSLC cache. That means you’re paying for the endurance rating. Frankly, we’re OK with that because this is one place you want that level of security. Standard drives often have comically high TBW for what users actually do with them, but this drive might actually see some serious writes over years of regular use. If that sounds like you, then you should definitely give the NAS 800 a serious look.

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Microsoft just made a major change to its storage policy affecting Microsoft 365 subscribers with shared accounts. According to the company, the Microsoft 365 Family, Premium, and Pro plans will move from an assigned 1TB of cloud storage for each user to a shared 2TB for all users. This means that a subscription shared across six users will have its total cloud storage capacity slashed by 66.6%. This change will take effect on subscription renewals after May 2, 2027, unless the subscribers change their plan earlier. Some affected subscribers might also receive bonus storage when their account switches to the share limit model, although the company did not mention its eligibility requirements.

The company said it made this change so that the cloud storage allocation for Microsoft 365 subscribers will automatically go where it’s needed, and that individual users are less likely to hit individual storage limits. Aside from that, it also said that unused storage can benefit the entire family, and that any additional storage that the main subscriber purchases will benefit everyone.

This new setup is indeed advantageous for subscribers who only have one power user that uses up the majority of the cloud storage capacity, while all the rest take up a fraction. It would also be cheaper for an individual who intends to use more than 1TB of cloud storage to just switch to the Microsoft 365 Family plan (which costs $129.99 annually) instead of getting the Microsoft 365 Personal plan ($99.99 annually) and paying an extra $9.99 per month or $119.88 per year to bring their total cloud storage capacity to 2TB. However, if you have four users under one account using 500GB each, you will be forced to purchase additional capacity, starting at $1.99 per month for 200GB.

While Microsoft hasn’t increased the prices of its subscription, this move simultaneously reduces the burden on its storage servers while forcing accounts with multiple large users to purchase storage separately. This seems like a reaction to the storage shortage hitting the industry, with hard drive prices surging by 46% from September 2025 to January 2026. Enterprise SSDs have been hit hard, too, with 30TB drives now costing $22,600 while supply remains sold out until 2027.

Affected users could change their cloud storage providers, but even Google has been affected, with the company cutting the free cloud storage limit from 15GB to 5GB pending extra security measures. Even Backblaze, which offers “unlimited” backups, updated its terms of service to potentially throttle or terminate accounts that exceed “typical usage patterns” or “places an undue burden.” Users who have grown tired of paying monthly to secure their data could alternatively set up a NAS and populate it with the best hard drives — although this might be pricey in the short term and requires some setup, it could potentially save you hundreds, if not thousands, of dollars in the long run.

Kioxia introduced its LD4-series solid-state drives (SSDs) in an E1.L form factor with capacities up to 122.88TB designed for high-density storage deployments in hyperscale data centers on Friday. The new drives use proven BiCS8 3D QLC NAND and are aimed at read-intensive workloads like AI data repositories and object storage, according to the manufacturer.

Kioxia's LD4-series SSDs rely on the company's proprietary platform complying with the NVMe 2.0e specification and featuring a single-port configuration along with select requirements of the Open Compute Project Datacenter NVMe SSD specification 2.6. Although Kioxia lists PCIe 5.0 compliance, the drives operate at PCIe 4.0 x4 speeds of up to 16 GT/s per lane, which provides a theoretical maximum bandwidth of approximately 7.88 GB/s in each direction. While the company currently offers capacities of up to 30.72 TB, it has validated an architecture capable of supporting 122.88 TB drives, though it never revealed when such drives are set to be available, something not surprising in a world where 3D NAND memory is sold in advance.

Interestingly, Kioxia did not disclose any actual performance characteristics of its LD4-series SSDs, including sequential read and write speeds, random read and write IOPS, or latency. The company also did not reveal their endurance ratings in drive writes per day (DWPD) or total bytes written (TBW), nor did it specify their power consumption. These characteristics are particularly important for hyperscale operators evaluating the cost, performance, and longevity of storage infrastructure.

The key selling point of Kioxia's LD4-series and its E1.L form factor — 318.75 mm length × 38.4 mm height × 9.5 mm thick — is its ability to house numerous 3D NAND flash packages on an elongated printed circuit board, thus enabling multiple drives to be installed in a thin 1U server, offering vast capacities. This enables system manufacturers among those who build OCP-compliant servers to maximize storage capacity without increasing rack space requirements, which is particularly important for large-scale storage deployments.

Kioxia is currently sampling 15.36 TB and 30.72 TB LD4 drives to select customers. The company has not disclosed when 122.88 TB configurations will become available or when the series will enter mass production. The drives will be demonstrated at the OCP Global Summit in San Jose in mid-October.

Normally, only a madman would even attempt to buy an SSD during a storage shortage. However, the WD Black SN770M 2TB has fallen to $259.99, just 8% above its original launch price. At this price, it is worth considering if your gaming handheld is running out of internal storage.

• Check out the WD Black SN770M 2TB deal on Best Buy

The WD Black SN770M, once one of the best SSDs, is an M.2 2230 drive, making it a perfect fit for popular handhelds like the Steam Deck, ROG Ally, Legion Go, and Claw. Currently, 2TB is the highest capacity available to consumers. Micron announced a 4TB M.2 2230 SSD not long ago, but it is limited to OEM models, so gamers will have to settle for 2TB for now.

The PCIe 4.0 SSD delivers sequential read and write speeds up to 5,150 MB/s and 4,850 MB/s, respectively. It is a perfect fit for modern handhelds that take advantage of the PCIe 4.0 interface. For the Steam Deck, however, which uses PCIe 3.0, the WD Black SN770M is a bit of overkill.

The WD Black SN770M remains a good option for gaming handhelds, even after the introduction of newer models like the Optimus GX 7100M. The SSD strikes a balance between price and performance, especially for the Steam Deck, which is limited by PCIe 3.0.

The WD Black SN770M came out three years ago with an MSRP of $219.99, but it typically hovered around $239.99. During the recent storage shortage, prices surged to between $349.99 and $399.99, so Best Buy's comparison value of $531.99 is heavily exaggerated.

For $0.13 per GB, the WD Black SN770M offers very good value, being only 8% above its pre-shortage retail price. The SSD is among the best deals available if you need a high-performance M.2 2230 SSD for your gaming handheld right now.

Seagate Technology and Toshiba are reportedly competing to acquire TDK's hard disk drive magnetic head business in a transaction valued at several billion dollars, reports Bloomberg. For Seagate, the acquisition would expand the supply of HDD heads that it also produces internally, but for Toshiba, TDK is the only way for it to get magnetic heads for its hard drives. If Seagate buys TDK's HDD heads operation, then Toshiba's HDD business will depend on supply from Seagate.

TDK is the world's only independent supplier of HDD magnetic heads and Toshiba's sole source of the components. By contrast, Seagate and Western Digital manufacture heads internally and also buy them from TDK if they need to. In recent years, TDK started to produce HDD heads for Seagate's drives that rely on heat-assisted magnetic recording (HAMR) technology, Western Digital's products featuring energy-assisted magnetic recording (EAMR), and Toshiba's HDDs based on microwave-assisted magnetic recording (MAMR) technology, which makes it an important supplier for all hard drive manufacturers.

Yet, while Seagate and Western Digital produce magnetic heads internally, they also source them from TDK when they need additional supply to respond to increases in demand. Toshiba, by contrast, depends entirely on TDK for these components. Access to TDK's technology is particularly important for Toshiba as while the company's next-generation 30TB-class HDDs are expected to rely on MAS MAMR technology, their successors will rely on HAMR. Meanwhile, developing write and read heads for HAMR is particularly hard and time-consuming, which makes TDK a key enabler for Toshiba's HDD business both for existing products (for which the company probably has long-term supply agreements) and future generations of hard drives that only exist in the roadmap.

Toshiba reportedly approached TDK about acquiring its HDD head operation in spring 2026. Seagate subsequently entered negotiations in summer with a higher offer, according to people familiar with the discussions, Bloomberg said. The potential acquisition could be worth as much as several billion dollars.

Control of TDK's magnetic-head operation could significantly alter the competitive balance of the HDD industry. The successful bidder would control the industry's only independent head supplier, which will potentially give it greater influence over pricing and make it more difficult for competitors to rapidly increase HDD output. Both Toshiba and Seagate are therefore reportedly concerned about maintaining access to TDK heads if the rival bidder acquires the business.

For TDK, a sale would provide an opportunity to exit an historically volatile, relatively low-margin business that requires continuous investment as magnetic recording technologies advance. The company has been directing more resources toward batteries, passive components, and sensors in anticipation of increased AI-related demand from devices such as smart glasses. Selling the HDD-head business could provide additional capital to accelerate investments in these areas.

Executives from Seagate, Toshiba, and TDK reportedly met in Tokyo last week to discuss mechanisms that could preserve supplies of magnetic heads, including a possibility of creating a joint venture. The negotiations remain preliminary and could ultimately produce no transaction. While Seagate and TDK reportedly declined to comment on the Bloomberg report, Toshiba denied that any meeting took place, as well as its plans to acquire HDD heads production capability.

It should be noted that any acquisition would likely face regulatory scrutiny because of the concentrated nature of the HDD market and TDK's unique position in it. TrendForce estimates that Seagate and Western Digital each account for approximately 45% of HDD shipments in terms of bits shipped, whereas Toshiba controls around 10%.

With desktops and laptops now almost certain to eschew an optical drive in 2026, keeping a USB optical drive and docking solution around will help you retain access to your collection of old software and media for years and PC generations to come. With this in mind, we've spotted a few flexible solutions on sale at Amazon that have wacky and seriously useful, yet odd, features that we just have to share:

The External CD/DVD Drive for Laptop, DVD Player for Laptop, 8 in 1 USB 3.0 Ultra-Slim Portable at $28.79.

The External CD DVD Drive, Portable CD DVD Driver +/-RW Burner with 2.5-inch SATA, SD Card Reader and USB A Type C 2.0 Hub at just $33.83. This model adds the convenience of a SATA drive dock to the equation.

There's also an External SUIDEK portable CD/DVD burner with USB hub and M.2 NVMe Dock for $39.99; this model swaps the SATA dock for an M.2 NVMe SSD dock, if you prefer.

• Check out the SUIDEK portable CD/DVD burner with USB hub and M.2 Dock
• Check out the SUIDEK External CD DVD Drive, USB 3.0 USB-C Portable CD DVD Drive for PC
• Check out the SUIDEK External CD/DVD DVD +/-RW Burner, Card Reader, and USB Hub

The cheapest SUIDECK drive still gives you lots of media connectivity options. This attractive portable device, with a silver metallic and black honeycomb finish, can read and write optical media at CD 24X and DVD 8X speeds. That's not all, as it also offers a USB 3.0 hub, 3x USB 2.0 ports, 1x USB 3.0 port, SD and TF card slot readers, and a USB-C port.

Compatibility of the SUIDEK External CD DVD Drive, USB 3.0 USB-C Portable CD DVD Drive for PC is also pretty extensive. For optical media, you can use CD±R/RW, CD-ROM, DVD±R/RW, DVD-RAM, VCD, and SVCD, the listing claims. Then, for systems/OS, you can plug this into Windows 11, 10, 8, 7, XP, Vista, Linux, and macOS 10.6 or above computers.

Those who feel that some SATA docking functionality will be useful might want to look more closely at this next SUIDECK optical drive and dock. For $33.83, you will have one portable device that can be used to read and write optical media at CD 24X and DVD 8X speeds. Again, there's a basic USB hub built in with 2x USB 2.0 ports, a USB-C port, plus SD and TF card readers. Extra appeal comes from the SATA 2.5-inch slot on top, which can be used for quick access to your old laptop hard drives or SSDs in what was once a very popular form factor.

This product listing isn't specific about things like DVD±R/RW or DVD-RAM support, but the exact same list of system/OS support is given: Windows 11, 10, 8, 7, XP, Vista, Linux, MacOS 10.6 or above.

All of the deals look like useful and bargain-a-licious Prime Day purchases. For $28.79, you can get the SUIDEK External CD DVD Drive, USB 3.0 USB-C Portable CD DVD Drive for PC, and it will read/write most of the common optical disks you will have lying around from the 2000s.

If your wants/needs expand to 2.5-inch SATA drive docking, then the $33.83 option gets the CD DVD Drive External, Portable CD DVD Driver +/-RW Burner with 2.5" SATA, SD Card Reader and USB A Type C 2.0 Hub, which is going to be hard to resist.

If the requirements expand to an optical drive dock supporting the more common modern M.2 NVMe SSD storage standard, the SUIDECK portable CD/DVD burner with USB Hub and M.2 Dock for $39.99 is the ultimate Swiss Army knife of portable external optical drives. We're also happy to see both brands' peripherals score 4.3/5 or better on Amazon reviews, as we haven't tested these ourselves.

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The AIpocolypse has consumed everything in its path, including the once-affordable high-capacity HDD. Newegg has a rare deal on a high-capacity 16TB external Seagate drive, knocking $100 off the price to bring it down to $449.99. That comes out to around $0.02 per GB, which is surprisingly sensible given HDD prices right now.

• Check out this deal on Newegg

The cheapest 16TB HDD we can find new right now is the IronWolf Pro at $599, which itself is on sale for 6% off. Around this point last year, before HDD prices started soaring, you'd be able to pick up around 28TB for $500. Now, most 16TB drives are around $700, with higher-end Exos drives pushing up above $800.

If you prefer internal storage, you can remove the enclosure, extract the drive, and put it in a case. Note that doing so will void your warranty, so although it's possible, you might want to rethink that move given how expensive HDDs are right now.

As with most external drives, the actual drive inside of the enclosure varies. Seagate doesn't list the speed of the drive inside, though many external HDDs run at 5,400 RPM. User reports online have shown both Barracuda and IronWolf Pro drives inside the Expansion Desktop, so naturally, your milage will vary.

You shouldn't expect great speeds from this drive. Most 5,400 RPM drives offer sustained sequential reads and writes around 100 MB/s. Thankfully, the USB 3.0 interface offers plenty of bandwidth to keep up with the slower drive. For long-term storage, speed shouldn't be an issue.

If you install the drive internally, you can use it for games, though you should stick to older titles. A lot of modern AAA games require an SSD, and even titles with HDD fallback like Ratchet & Clank: Rift Apart struggle on slower 5,400 RPM drives.

Seagate ships the drive formatted to ExFAT, so it'll work with virtually any platform out of the box. Of course, you're free to reformat the drive to any file system you want.

At $449, the 16TB version of this drive is the one to buy. Both the 12TB and 14TB versions are more expensive at $619.99 and $660, respectively, while the 26TB version is $1,179.99.

If you're looking for more savings, check out our Best PC Hardware deals for a range of products, or dive deeper into our specialized SSD and Storage Deals, Hard Drive Deals, Gaming Monitor Deals, Graphics Card Deals, gaming chair, or CPU Deals pages.

Toshiba has spent approximately ¥60 billion ($380 million) to expand its hard drive assembly capacity in the Philippines, doubling its production capacity for nearline HDDs in fiscal 2027 compared to fiscal 2025, reports Nikkei. The capacity expansion coincides with Toshiba's plans to launch next-generation 30TB-class hard disk drives in 2027 and will prepare the company for 65TB-class HDDs by 2030 and 100TB-class drives in the future.

As part of the expansion, Toshiba has installed additional manufacturing lines at its Philippine Laguna Technopark (LTI) facility to build nearline hard drives and prepare it to produce next-generation HDDs that increase storage capacity per drive by as much as 40%. The 40% claim clearly points to the company's next-generation M12-series hard drives that rely on microwave-assisted magnetic recording (MAMR) technology, use up to 11 platters, and offer capacities of over 30TB.

Meanwhile, as the new product lines have already been installed and the first shipments from them have been made (meaning that the new production lines are at least partly qualified), the ramp of next-generation drives can start anytime.

In addition, the company plans to introduce more automation in its cleanroom operations and drive inspection, measures aimed at improving manufacturing yields amid increased output. The new automation will also reduce the requirement for additional employees by 40%.

The project represents the company's first substantial HDD manufacturing investment in around five years and comes as demand for nearline drives is skyrocketing. So far, both Seagate and Western Digital have enjoyed strong demand for 30TB and 40TB-class HDDs from the AI sector. While Toshiba is lagging with 24TB CMR and 28TB SMR hard drives, it has also sold out every single unit it has produced in recent quarters. Arguably, all three HDD makers are late to expand their production capacity.

Meanwhile, the expansion is only one step in Toshiba's longer-term HDD roadmap. The company recently reiterated plans to introduce its 40TB-class HDDs with up to 12 disks inside in 2027, so the expansion will be instrumental for the ramp of these products as well. Yet, it remains to be seen whether the company will at least formally introduce its 12-platter 40TB-class models in calendar year 2027, as next year seems to be dedicated to the ramp of the company's 30TB-class M12-series of HDDs.

The company intends to continue investing in manufacturing capabilities to begin volume production of 65TB-class HDDs around 2030, followed eventually by 100TB-class drives, according to the report. These products will address growing storage requirements in AI and other large-scale data centers. Toshiba also expects the new production lines and next-generation HDDs to help it increase its market share from around 10% today, measured by exabytes shipped, to 30% in the 'medium term,' according to the report.

Owning a PC gaming handheld is quite handy, but sometimes involves playing uncalled-for matches of Tetris with the internal storage, especially as games get larger. Storage expansion often comes by way of microSD cards, which can be added without opening the console, but can be slower than NVMe SSDs. BiWin's CL 100 Mini NVMe SSD tackles both those problems, arriving in a 15 x 17 mm form factor with custom casing. It's effectively the size of a microSD card.

The diminutive unit was spotted earlier in the year, but hadn't been given a name or selling price until recently. The unit is currently bespoke to BiWin's OneXPlayer consoles (OneXFly Apex/Air, OneXPlayer 3, X1 Air, X2 Mini, and Super V/X) as well as the GPD Win5. These systems have hardware slots specifically for this size drive that you could insert like an SD card. For comparison, the M.2 2230 drive inside the Steam Deck and other portables is, unsurprisingly, 22 x 30 mm — much larger, and it requires opening the machine, plus one of those annoying little M.2 screws.

• 512 GB at Amazon UK
• 1 TB at Amazon UK
• 2TB unit only available from third-party sellers at Amazon UK
• Drive reader at Amazon UK

Despite the physical format being manufacturer-specific, the CL 100 Mini appears to be a standard NVMe 1.4 drive with a PCIe 4.0 interface. The installation instructions are simple. The Silicon Motion SM2268XT2 controller is a standard NVMe affair, and it's also used in standard M.2 2280 Crucial and Kingston drives, among others.

Despite being connected to only one slab of Samsung V8 TLC NAND, it can still reach 3700 MB/s on sequential reads and 3400 MB/s for writes, both excellent figures as far as the needs of gamers are concerned. If you want to use the BiWin CL100 Mini as an external drive, the company offers a mini-SSD reader with a USB-C port, though speeds are limited to around 3000 MB/s in either direction.

You can get the drive from the BiWin store on Amazon, in 512 GB for 139.99€ and 1 TB for 259.99€. There's also a 2 TB unit advertised, though that one is only available from third-party sellers for an arguably disproportionate 699.99€. The smaller units are roughly in line with equivalent M.2-2230 units from reputable manufacturers. Meanwhile, the reader unit is priced at 79.99€.

Micron this month filed a lawsuit against China's 3D NAND champion YMTC, accusing it of poaching its leading engineers, illegally obtaining its NAND memory know-how from them, and then using that information to build its own non-volatile memory as well as its patent portfolio. The Boise, Idaho-based company further alleges that YMTC uses patents granted to its former employees to accuse Micron of patent infringements in various jurisdictions.

To assemble a comprehensive IP portfolio that would cover everything from essential technologies to sophisticated manufacturing methods quickly, as well as to ensure that its patents overlapped with those of other 3D NAND manufacturers to enable it to attack Micron, the firm asserts YMTC opted for a rather simple, yet effective strategy: It poached engineers from Micron, then made them patent either standard essential inventions or inventions that closely resembled those they worked on while at Micron.

To leave Micron without being asked questions, its former employees cited a broad range of personal or family reasons for their resignations and even did not update their LinkedIn profiles to reflect their new roles at YMTC. These employees had confidentiality obligations that continued after termination of their employment and proscribed them from using, disclosing, or possessing Micron’s confidential information. Meanwhile, Micron did not really investigate the whereabouts of its former employees and "had no reason to suspect YMTC itself" of planning to use its confidential information because "YMTC did not have any material market share in the industry.”

We are all used to cut-throat competition on the memory market as leading producers of DRAM and NAND try to win market share from each other and maintain profitability at the same time. These companies have broad cross-licensing agreements to neutralize direct patent wars that can result in devastating injunctions that could paralyze fab operations and eventually lead to assured mutual destruction. However, this does not seem to be the case for emerging competitors from China, ChangXin Memory Technologies (CXMT) and Yangtze Memory Technologies Co. (YMTC), both established in 2016, which are increasingly attacking Micron in various courts, perhaps making pre-emptive strikes to avoid the destiny of their Chinese counterpart, Fujian Jinhua.

Using Micron's 3D NAND know-how against Micron

In its lawsuit against YMTC, Micron asserts that Yangtze Memory's patent campaign against Micron largely relies on patents that were granted to former Micron employees. Furthermore, Micron alleges that former employees brought its 3D NAND know-how to YMTC and subsequently developed patents covering related or overlapping technologies, which essentially means that Yangtze Memory has built its patent portfolio using Micron's intellectual property, which is why Micron claims that YMTC patents belong to Micron and therefore cannot be used against it.

"For example, these individuals include Daesik Song, Wenxi Zhou, and Hua Tan," Micron's lawsuit reads. "Each of these employees owed Micron contractual obligations to keep trade secrets confidential, had access to certain of the Micron Trade Secrets further described below while employed at Micron, and on information and belief, each joined YMTC shortly after leaving Micron. Each of these employees also regularly accessed one or more of the Trade Secrets that were located on servers in Boise by accessing Micron's highly confidential technical materials relating to its test and/or production nodes."

Micron's allegations in the new complaint go well beyond simple claims that its former employees brought manufacturing expertise to YMTC, something that happens often. The company alleges that YMTC systematically obtained confidential 3D NAND and memory technology from former Micron engineers and incorporated that knowledge into its manufacturing processes starting from its 64-layer 3D NAND, memory products, and, most importantly, its patent portfolio. Micron says it began to uncover the alleged scheme after YMTC sued it for patent infringement in California in November 2023, when it noticed that several patents asserted against it named former Micron engineers as inventors.

In its complaint, Micron identifies a number of its former employees who subsequently became inventors on YMTC patents, including Hongbin Zhu, Jun Liu, Yushi Hu, Qian Tao, Changhyun Lee, Daesik Song, Wenxi Zhou, and Hua Tan. According to Micron, these engineers had access to different classes of confidential technology that covered a broad range of 3D NAND-related know-how, including high-aspect-ratio etching, replacement gate processing, multi-deck connections, pillar shaping and cleaning, and memory I/O circuitry, among others.

Patent records independently confirm an important part of Micron's allegations: several former Micron engineers later became inventors in YMTC patents that YMTC eventually used against Micron. In general, this does not prove any misappropriation: engineers routinely change employers and continue to invent in their areas of expertise, but Micron alleges that some of these patents cover inventions conceived or developed while their inventors still worked for Micron, which is why it is asking courts to transfer ownership of these patents from YMTC to Micron.

One of the clearest examples involves Hongbin Zhu, who left Micron in September 2017 and subsequently became an inventor in numerous YMTC patent applications. One family originates from the international patent application PCT/CN2018/101482, filed on August 21, 2018, and includes three patents. Micron's complaint alleges that these patents relate to technology Zhu 'learned of, worked on, and/or conceived while at Micron' and asks the court to transfer their ownership from YMTC to Micron. The same family also includes two additional patents that YMTC asserted against Micron in its California infringement lawsuit. Micron has already challenged ownership of these two patents in that litigation and claimed that Zhu invented the underlying technology while employed by Micron and had assigned his rights to the company.

Daesik Song provides another connection between Micron's allegations and YMTC's patent enforcement campaign. Song previously worked at Micron on memory I/O technology and later became an inventor on a patent titled 'Double Data Rate Circuit and Data Generation Method Implementing Precise Duty Cycle Control.' YMTC asserted the '851 patent against Micron in the Eastern District of Texas, yet Micron now alleges that it is actually the rightful owner of the patent because Song's invention-assignment agreement transferred inventions conceived during his Micron employment to Micron. The company is therefore asking the Idaho court to transfer legal title to the '851 patent from YMTC to Micron.

The Song connection also extends beyond the United States. In Europe, YMTC owns European patent EP 3 909 047, which covers the same invention as the '851 patent, and uses it against Micron in its UPC in Düsseldorf and U.K. litigations. Thus, YMTC is enforcing different members of the same invention family against Micron in Texas, the UPC, and the U.K. while Micron alleges that the U.S. patent from that family actually belongs to Micron. That does not automatically mean Micron owns the EP '047 since the U.S. and Europe are different jurisdictions, but it demonstrates how Micron's ownership allegations intersect with YMTC's international patent campaign.

There are additional connections. Former Micron engineers Yushi Hu and Qian Tao are named as inventors on two patents that YMTC asserted in California, while Jun Liu, Qian Tao, and Yushi Hu are all inventors on another patent asserted against Micron there. Changhyun Lee is an inventor on US 11,468,957, also part of YMTC's California case. Meanwhile, Wenxi Zhou appears on a YMTC patent family that covers barrier layers for word-line contacts, including US 12,094,767.

The European cases provide a somewhat narrower connection. Of the three European patents YMTC is asserting through the UPC and UK proceedings, EP 3 909 047 is directly relevant because it names former Micron engineer Daesik Song. The other two — EP 3 850 660, which names Qinxiang Wei, Jianhua Sun, and Ji Xia, and EP 4 236 650, which names Zilong Chen and Xiang Fu — do not name any of the former Micron engineers identified in Micron's complaint. Meanwhile, YMTC has also filed eight patent cases against Micron in China, three in Beijing and five in Shanghai, although we have not found a reliable public list of the eight Chinese patents involved, so it is not yet possible to determine whether they include Chinese patents of YMTC's inventions in the U.S. and Europe.

To sum up, the list of patents and YMTC engineers reveal a much more complicated dispute than an ordinary patent fight between two memory manufacturers. In less than a decade, YMTC has built an international patent portfolio and is attempting to enforce it against Micron across the United States, China, Germany, the UPC, and the U.K. Several of the patents used in that campaign are assigned to engineers who previously worked for Micron. Furthermore, Micron now alleges that at least some of those inventions were conceived while at Micron or using its trade secrets, so at least in some cases these patents belong to Micron, according to the company's complaint.

In short, Micron's main allegation is not that YMTC obtained its manufacturing know-how through former employees, but that some of this know-how was ultimately converted into YMTC intellectual property that YMTC later used to sue Micron itself. Hence, if Micron proves to the courts that YMTC's inventions are in fact Micron's inventions, then the whole Yangtze Memory campaign falls apart. However, the decision by the Munich I Regional Court looks rather alarming for Micron, as the company has so far failed to persuade the court that it not only did not infringe any YMTC patents, but that the very patents in question were obtained illegally.

All-out war

YMTC sued Micron in the Northern District of California in early November 2023, alleging that Micron's 3D NAND infringed eight U.S. patents. In early 2024, YMTC brought three additional patent cases against Micron in Beijing, then followed up with another California lawsuit in July that asserted another 11 U.S. patents against Micron’s 3D NAND and DDR5 products. In September 2024, YMTC expanded its Chinese campaign with five more patent cases in Shanghai. The dispute became global on October 6, 2025, when YMTC simultaneously launched another wave of litigation, asserting eight patents in the Eastern District of Texas, three patents in the U.K., three European patents before the Unified Patent Court in Düsseldorf, and five patents before the Munich Regional Court.

By then, what had begun as an eight-patent U.S. dispute had evolved into a multi-jurisdictional patent war covering dozens of patents and some of Micron's most important NAND products. Hence, Micron had to start responding. On October 18, 2024, the company filed a counterclaim alleging that it is the true owner of the US 10,879,254 and US 11,581,322 patents (more on this later). Then, almost two years after YMTC first sued Micron, the company filed the case on October 7, 2025, asking the U.S. District Court for the Northern District of California to issue a declaratory judgment of non-infringement concerning YMTC patents, which essentially means that Micron asked the court to rule that its patents did not infringe certain YMTC patents. These actions were barely a defense from YMTC's all-out patent war.

However, having spent nearly three years primarily defending itself and challenging YMTC's patents, Micron decided to respond more vigorously, which it did in its lawsuit filed with the Boise, Idaho, court on September 15. In the new lawsuit, Micron alleges that YMTC systematically obtained Micron's 3D NAND manufacturing know-how through former Micron engineers and then incorporated that information into both YMTC's manufacturing processes (64-layer, 128-layer, 232-layer, and subsequent nodes) and its patent portfolio. The alleged trade secrets cover multiple aspects of contemporary 3D NAND production, including high-aspect-ratio etching, replacement gate processing, multi-deck connections, pillar formation, and other manufacturing techniques.

Micron claims that its former employees who had access to this information later worked on similar technologies at YMTC and became inventors in YMTC patent applications. More importantly, some of these patents or their family members were subsequently used by YMTC against Micron, which essentially means that YMTC used patents granted to Micron's former employees against Micron itself. In many cases, YMTC allegedly poached Micron engineers who had previously developed and patented certain technologies at Micron, then tasked them with working on similar technologies and filing new YMTC patents covering essentially the same technical solutions. As a result, Micron now claims that several of the underlying inventions actually belong to it.

Back in Europe, Micron launched its own patent offensive against YMTC and companies that sell products which allegedly use the disputed technologies. In July, Micron sued YMTC in the Munich Regional Court, where it named Apacer, Lexar, and Ultron as co-defendants. In addition, it took a separate U.K. High Court action targeting YMTC alongside its partners Apacer, Lexar, and TeamGroup (note that TeamGroup is one of the SSD makers that from time to time uses different memory and even controllers on the same SSD models).

The German ruling

Before we proceed with a rather unprecedented decision of the Munich I Regional court, let us explain the difference between the patent and utility model as neither the U.S. nor the U.K., nor Canada, support the utility model system.

A patent protects major technical inventions across process technologies, tools, and materials for up to 20 years, but it requires a rigorous step-by-step patent office examination that typically takes years and significant expense to obtain. By contrast, a utility model protects incremental, practical mechanical or structural improvements to physical products for a shorter duration (usually 5 to 10 years). It is granted rapidly within months and at a fraction of the cost because it involves a lower inventive threshold and skips substantive examination prior to registration. While most patent offices register utility models without checking whether the idea is actually new, the validity of a utility model remains uncertain until enforcement. This is where YMTC prevailed to a degree that nobody expected.

In fact, YMTC has so far failed to gain any substantial court victory in the U.S., but it scored its first major victories in its German litigation against Micron in September, when the Munich I Regional Court ruled that Micron infringed two YMTC German utility models and granted injunctions against the company. The two utility models — DE 20 2020 006 166 U1 and DE 20 2021 004 551 U1 — cover 3D NAND-related to staircase structures and barrier layers for word-line contacts, respectively. The injunctions prohibit Micron from offering and selling products that infringe the two utility models in Germany. Meanwhile, the court has adjourned decisions on three infringement actions: it did not reject the other three, but simply has not resolved them.

Normally, this would not be a problem for Micron's clients, as unlike injunctions by the U.S. ITC, these rulings in the European Union typically have no effect on downstream entities, so Dell, Lenovo, and other PC OEMs can continue selling PCs containing violating hardware. However, it is possible that this particular decision could affect Micron's downstream partners, effectively prohibiting them from selling systems with Micron's 3D NAND inside. As a result, the injunctions could disrupt sales of PCs, SSDs, servers, and other products containing the affected Micron NAND in Germany.

Micron has appealed the decisions and is challenging the validity of the rights, so the September rulings represent first-instance victories for YMTC rather than the end of the dispute. Three other Munich cases brought by YMTC — including one that involves a European patent — have not yet produced infringement decisions. Yet, the existing decision shows that courts can side with Yangtze Memory and rule that Micron uses YMTC's intellectual property illegally.

Normally, this would be a 'local' problem for Micron. However, it is important to mention that some of the technologies and patent families involved in the European litigation overlap with those asserted in the United States. Several of them name former Micron engineers as inventors.

In fact, both German utility models on which YMTC just won injunctions appear to belong to patent families that involve former Micron engineer Wenxi Zhou, with corresponding U.S. patents being used by YMTC against Micron in Texas. This becomes particularly important in light of Micron's new allegations that former employees brought its 3D NAND know-how to YMTC and subsequently developed patents covering related technologies. If YMTC can win a litigation in Germany, can it also prevail elsewhere using the same patent families?

Summary

The conflict between Micron and YMTC emerged amid the escalating U.S. – China semiconductor confrontation. In October 2022, the U.S. imposed sweeping restrictions on exports of advanced semiconductor manufacturing equipment and technology to China, and in December 2022, the U.S. Department of Commerce added YMTC to its Entity List, which severely restricted the company's access to American fab tools. China responded with pressure on Micron: in May 2023, the Cyberspace Administration of China concluded that Micron had failed a cybersecurity review and prohibited operators of critical information infrastructure from purchasing affected Micron products.

The commercial conflict between the two memory makers eventually moved into the courts, with YMTC accusing Micron of patent infringement and Micron largely defending itself rather than launching a comparable patent offensive of its own. Micron’s new complaint in Boise, Idaho, may explain this strategy: the American memory maker not only seeks to defend itself against YMTC's infringement claims, but also alleges that some of the patents YMTC is using against it incorporate Micron’s confidential technology or actually belong to Micron itself. But while Micron can potentially prevail in the U.S. and perhaps in Europe and the U.K., China represents a different challenge, as the legal battle between the two memory makers may well be considered a part of the broader geopolitical confrontation between the U.S. and China.

Sony launched the world’s first CD player on this day in 1982, kickstarting the compact disc digital audio era. The Sony CDP-101 was released to consumers in Japan, priced at JPY 168,000. That converts to $1,060 at today’s exchange rate, and is about $3,700 adjusted for inflation. CD players were meant to be a worldwide launch on October 1, 1982, but tech partner Philips didn’t have its CD100 ready, so Sony agreed to limit this initial event launch to Japan. Six months later, U.S. and European consumers would get their chance to buy a CD player, starting March 1983.

As for this first CD player hardware release for consumers from Sony. It wasn’t perfect, of course, and Wikipedia points out one particular limitation of the CDP-101: It had just one DAC for both left and right audio channels due to the high cost of these converters. Without sample-and-hold circuitry, this meant the stereo channels were approximately 11 μs out of sync.

Before CDs, home hi-fi setups of the era were typically built around vinyl records and compact audio cassette tapes. For a full set of separates, an enthusiast would also add a radio tuner, an amplifier, plus speakers - of course. Users of these older established pre-recorded audio media would have to cope with music affected by various imperfections over time. Vinyl sound quality would be a battle to maintain against the challenges of dust, scratches, warping, and wear. I remember pre-recorded cassettes had other problems, the major one for me being the variable quality of the tapes used by the distributors.

So, CDs came with many attractive promises, most importantly in the context of the early 1980s – providing digital music data that was read by a laser and wouldn’t wear. CDs also offered near-instant track selection, skipping, and replay. But most consumers would have to wait a few years: firstly for the price of player hardware to approach an acceptable level, and secondly for CD albums to become the norm for new releases and classic remasters.

Sony worked with CBS to have 50 CD albums on the shelves when the CDP-101 debuted in Japan. You’d think that six months later, when Philips joined in, and we saw the worldwide launch, that the catalog would have grown. Surprisingly, the ‘western’ launch was backed by just 16 titles.

It wouldn’t be until the mid-1980s when landmark DDD releases arrived and player prices dipped to much more acceptable levels that CDs would become established as a hi-fi staple. At around the same time, we started to get computers with built-in CD-ROM drives, but these would only start to become common from the early to mid 1990s and the dawn of the multimedia PC era.

If you are a retro tech fan who would be interested in buying a Sony CDP-101 before they all end up in museums, we noticed that you can buy them on eBay. At the time of writing, there were several of these 1982-vintage CD players for between $600 and $800.

The good news is that Sandisk is still putting out SSDs for consumers, and these are not just cheap replacements. The Optimus GX Pro 850P is a bona fide high-end Gen 4 SSD that puts Sandisk’s name on the WD Black SN850X’s legendary design. This means DRAM, TLC flash, and good performance for any role.

Like the Black SN850P, which is a Black SN850X made with a heatsink and for the PS5, the 850P is made for the console. Its heatsink is excellent, and it would fit right into your desktop PC, too. We wouldn’t recommend shucking it for use in a laptop, but theoretically it could work there as well. Our main concern would be the pricing, which is a bit steep – this is a nice drive, but you’ll pay a premium for it.

Sandisk Optimus GX Pro 850P Specifications

The Sandisk Optimus GX Pro 850P is available at the same capacities as its WD Black SN850P forebear: 1TB, 2TB, 4TB, and 8TB. This also matches the original WD Black SN850X and its later 8TB SKU. Prices at the time of review for the Optimus GX Pro 850P are $309.99, $609.99, $1,139.99, and $2,249.99. These prices are well above the $234.99, $494.99, and $1,019.00 that the Black SN850P is currently demanding. We think the prices will come down on the Sandisk drive, but be aware of the comparable alternatives when making a purchase.

The drive can reach up to 7,300 / 6,600 MB/s for sequential reads and writes and up to 1.2 million random read/write IOPS. This performance is at the top for a Gen 4 drive and, frankly, is capable of delivering an excellent experience even for heavier workloads. The drive’s warranty is standard at five years with 600TB of writes for every TB of capacity. The Optimus GX Pro 850P supports data-at-rest encryption through TCG Opal v2.01, but this is not explicitly listed for the SN850P, likely as this model is designed for use in the PS5.

Sandisk Optimus GX Pro 850P Software and Accessories

Sandisk fully supports its drives with downloadable software. For the Optimus GX Pro 850P this includes the Sandisk Dashboard, which is Sandisk’s version of WD’s Dashboard, and Acronis True Image for Sandisk. The former is an SSD toolbox with all of the expected features: drive health and SMART monitoring, firmware updating, performance testing, etc. Acronis True Image is OEM-licensed software used for backing up files and imaging drives.

Sandisk Optimus GX Pro 850P: A Closer Look

The Optimus GX Pro 850P is designed to specifically fit into the PS5 with an effective heatsink. The bare drive underneath is single-sided at 1TB and 2TB but double-sided at 4TB and 8TB. For that reason, the rated height is larger for the latter two SKUs. In general, this should not be an issue for fit in desktop PCs. The heatsink itself is finned for extra surface area for better heat dissipation and should keep the drive cool even under harsh conditions. It does not have RGB, unlike the WD Black SN850’s heatsinked SKU.

The drive label gives some additional information, such as a rating for 3.3V / 2.8A. This is ~9W, which matches the drive’s highest reported power state. This is certainly higher than the ~5W we see for many DRAM-less drives, which have half the flash channels on top of not having DRAM to worry about, but it is not enough to be a problem with this heatsink.

The Optimus GX Pro 850P has a relatively standard SSD layout with an SSD controller, a DRAM module, power management circuitry, and two NAND flash packages. The larger, double-sided versions of the drive will have more NAND flash packages, with two additional packages on the back. We’ve covered the controller and its iterations in the past. The DRAM, for what it’s worth, is DDR4, which is serviceable for the role volatile memory plays on an SSD: mostly as a metadata cache. The one caveat here is that our 2TB drive only has 1GB of DRAM, which is one-half the usual and likewise one-half of what we had on our 2TB WD Black SN850X sample. In practice, this should have no impact on intended workload performance and could potentially reduce cost a small amount.

The flash is potentially more interesting, as it could be the expected BiCS5, or it could have been updated. The 8TB WD Black SN850X uses BiCS6, and it can make sense to cycle in newer flash later on in a product’s lifetime. The Optimus GX Pro 850P is essentially in that line. What we can say for sure is that the flash on here was manufactured more recently than the flash on the Black SN850X samples we’ve reviewed at both capacities – newer in production date, not necessarily in generation – but the performance is close enough that there would be little perceptible difference even if it were generationally different. This drive is at the edge of what you can get out of this controller technology and Sandisk could also choose to tune it specifically for this performance range, so at the end of the day one could say this is, effectively, equivalent to the WD Black SN850X with BiCS5 TLC flash.

We believe our sample is still using BiCS5 anyway – the coding’s sixth character “C” implies that – but that statement applies to any potential BiCS6 swap. In this case, moving to newer BiCS5 means a higher I/O rate, 1,200 MT/s to 1,600 MT/s. The former is plenty to saturate a PCIe 4.0 link with an eight-channel controller like the 850P’s, but putting in newer flash makes sense from a supply perspective. Higher MT/s flash can have lower latency and potentially better power efficiency when run at a lower MT/s, but we don’t believe either is a motivation here. Real-world impacts are, again, minimal, with minor exceptions that might not exist if we were comparing to a current Black SN850X.

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Comparison Products

The Sandisk Optimus GX Pro 850P is Sandisk’s take on the WD Black SN850P, which in turn is a PS5 version of the Black SN850X, so we have to compare it to that latter drive. The stiffest proprietary competition is from Samsung with the 990 Pro. Alternatives with DRAM but different hardware include the Crucial T500, the Adata Legend 960 Max, the TeamGroup G70 Pro, and the Inland Gaming Performance Plus. To keep things honest, we also want to compare faster DRAM-less drives that have historically been great for the PS5. These include the Addlink A93 (4TB) and the WD Black SN7100.

Trace Testing — 3DMark Storage Benchmark

Built for gamers, 3DMark’s Storage Benchmark focuses on real-world gaming performance. Each round in this benchmark stresses storage based on gaming activities including loading games, saving progress, installing game files, and recording gameplay video streams. Future gaming benchmarks will be DirectStorage-inclusive and an evaluation for future-proofing is included where applicable.

Is the 850P a good game drive? In our estimation, yes. It beats the original Black SN850X, due in part to firmware maturity and/or the newer BiCS5 – we would expect these two to be comparable if the Black is or has been updated – and it is also faster than popular DRAM-less options like the A93. In general, we think going with something DRAM-less, like the A93, is a good way to save some money if you’re buying an SSD just to host games. This approach extends even to the Black SN7100, which struggles on this list against the largely DRAM-equipped competition, as it still scores pretty well. We consider 45µs or better to be excellent for load times.

Trace Testing — PCMark 10 Storage Benchmark

PCMark 10 is an industry standard trace-based benchmark that uses a wide-ranging set of real-world traces from popular applications and everyday tasks to measure the performance of storage devices. The results are particularly useful when analyzing drives for their use as primary/boot storage devices and in work environments.

For general application use, we are a little more disappointed. The 850P ends up in the middle of the pack, although its results are still quite good. This will beat most DRAM-less drives, although it falls behind the Black SN7100, as that drive uses very responsive BiCS8 flash. This makes it clear that the 850P is using older BiCS flash, which doesn’t have the same latency edge. This isn’t the worst trade-off if you’re looking for a full-fledged SSD with eight flash channels and DRAM – this drive will sustain better over time and through heavier workloads. Again, anything at or below 45µs for latency is good in our book, so this would be perfectly suitable as an OS drive.

Console Testing — PlayStation 5 Transfers

The PlayStation 5 is capable of taking one additional PCIe 4.0 or faster SSD for extra game storage. While any 4.0 drive will technically work, Sony recommends drives that can deliver at least 5,500 MB/s of sequential read bandwidth for optimal performance. Based on our extensive testing, PCIe 5.0 SSDs don’t bring much to the table and generally shouldn’t be used in the PS5, especially as they may require additional cooling. Check our Best PS5 SSDs article for more information.

Our testing utilizes the PS5’s internal storage test and manual read/write tests with over 192GB of data both from and to the internal storage. Throttling is prevented where possible to see how each drive operates under ideal conditions. While game load times should not deviate much from drive to drive, our results can indicate which drives may be more responsive in long-term use.

The 850P should be, by most accounts, the definitive PS5 SSD. We’ve had the Black SN850X as our best SSD for the PS5 for quite a long time, although the SN850P is the PS5-specific model. The Black SN850X simply delivers a similar experience to the SN850P at a lower price point. Why is this the best SSD for the platform? Well, you get top-tier Gen 4 performance with reliability and an excellent heatsink. All of this still applies to Sandisk’s 850P.

Now, a DRAM-less alternative with half the flash channels – which means it runs cooler – like the A93 seems to be more sensible. It’s less expensive, and the PS5 doesn’t benefit from more performance than it provides. The argument here is therefore more on reliability and, possibly, consistency. The 850P can manage more flash at once – which actually is ideal for larger capacities, including 2TB for this generation – and it also has DRAM.

Many enthusiasts still want DRAM as it can improve performance and endurance. Keep in mind that our A93 sample is the 4TB model, which its controller can address thanks to a revision made for that purpose. A four-channel drive is still at its best with up to four dies per channel, or 16 in total, which works out to 2TB with 1Tb dies. Going past that doesn’t really deliver more performance, and having an eight-channel controller is preferable at higher capacities. A stronger argument would be this: the 850P is a quality, mature product that could act as an investment. Considering that a 2TB Black SN850X bought at its lowest price beats the stock market right now, that’s not as crazy as it once sounded.

Our take is that, for a PS5, you really can get anything. If you’re set on a quality drive, though, this one is basically as good as it gets. You’re here for the numbers, though, and it only wins in transfers to the drive, and not by much. That’s valid, but with more wear and a fuller drive, it is more likely to maintain peak performance for longer. So, don’t buy this drive for faster game load times or FPS, because you won’t get that here.

Transfer Rates — DiskBench

We use the DiskBench storage benchmarking tool to test file transfer performance with a custom 50GB dataset. We write 31,227 files of various types, such as pictures, PDFs, and videos to the test drive, then make a copy of that data to a new folder, and follow up with a reading test of a newly written 6.5GB zip file. This is a real-world type workload that fits into the cache of most drives.

Our DiskBench test gives a good measure of real-world performance with a mixed file load, with Gen 4 expectations around 2 GB/s for copies and writes and 4 GB/s for reads. Writes are going to be slower than reads and can help cap copy performance. The 850P does nothing unusual here, coming in at numbers close to these. We tend to put the most weight on copy performance and, here, the 850P manages to come in second behind only the T500. This makes sense as the T500 has newer flash with more planes, which helps it eke out more bandwidth. The Black SN7100 also has newer flash, specifically a newer form of BiCS, which keeps it competitive. Still, the 850P impressively beats the Black SN850X by a significant amount – perhaps due to firmware maturity and/or newer BiCS5 – and the 990 Pro as well.

This is an important result because most of what people use storage for ultimately comes down to transfers like these. Files between drives. Backups. Updating software. You’re not going to have a lot of transfers going on at once with a high queue depth, and if you’re working with smaller files, you are not going to get near the theoretical throughput. So, the 850P certainly earns the mantle of being a high-end Gen 4 drive. On the other hand, even the DRAM-less A93 is not that much slower. If you’re someone who does a lot of transfers, the added time could add up, though.

Synthetic Testing — ATTO / CrystalDiskMark

ATTO and CrystalDiskMark (CDM) are free and easy-to-use storage benchmarking tools that SSD vendors commonly use to assign performance specifications to their products. Both of these tools give us insight into how each device handles different file sizes and at different queue depths for both sequential and random workloads.

The 850P performs very closely to the Black SN850X in ATTO, as expected. We see no real anomalies here. The drive is very consistent, which makes for a reliable user experience regardless of workload type. It is easy to notice, however, that the 850P and Black SN850X have weaker performance between the 512B and 2KiB block sizes, closer to the Legend 960 Max and WD Black SN7100. We would chalk this up to the controller technology for the WD and Sandisk drives – they all use proprietary ones with the same foundation – with the Legend 960 Max being the singular SMI-based drive.

We’ve found historically that drives may show up weaker here in ATTO as indicative of a trade-off. This is because, generally, we think in terms of 4KiB – a typical cluster and sector size that is used for performance metrics everywhere – which is a logical page downstream from the 16KiB physical pages that modern flash uses. Handling smaller reads/writes could increase memory load and can increase latency. However, focusing on 4KiB and larger block sizes makes more sense for a variety of workloads, and performance is not the only factor. A manufacturer also has to consider power consumption and wear, for example. So there may be good design reasons for this behavior.

If we move on to CDM to see performance at 4KiB, at a typical queue depth of 1, the 850P is average with reads and on top with writes. Anything at or below 45µs for reads is pretty good, and the drive competes well. The SN7100 is in a class of its own with its BiCS8 flash. For writes, which are often less important, we see strong numbers from most drives. The DRAM-less A93, the SMI-based Legend 960 Max, and the proprietary 990 Pro are on the weaker end. Generally speaking, this does not indicate a problem with the drive at this level and could be a facet of the controller, the flash, or both, often also as a trade-off. What we can say is that the 850P is stellar here, which certainly makes it more attractive for use in a NAS, for caching, and for workloads that are not found in the PS5. That’s not a knock – it simply illustrates the drive’s heritage and underlines that this drive could be good anywhere.

Sustained Write Performance and Cache Recovery

Official write specifications are only part of the performance picture. Most SSDs implement a write cache, which is a fast area of pseudo-SLC (single-bit) programmed flash that absorbs incoming data. Sustained write speeds can suffer tremendously once the workload spills outside of the cache and into the "native" TLC (three-bit) or QLC (four-bit) flash. Performance can suffer even more if the drive is forced to fold, the process of migrating data out of the cache in order to free up space for further incoming data.

We use Iometer to hammer the SSD with sequential writes for 15 minutes to measure both the size of the write cache and performance after the cache is saturated. We also monitor cache recovery via multiple idle rounds. This process shows the performance of the drive in various states including the steady state write performance.

We’ll start with the 850P’s fastest mode in the cache: over 6.46 GB/s for just over 92 seconds. This is a 595GB cache, more or less exactly matching the Black SN850X. A drive with 3-bit TLC cache can handle up to one-third its actual size, so this is smaller than what’s possible but still large in the grand scheme of things. It’s more than suitably large to cache even large file writes, which means it can be used for things outside of gaming. This is reinforced by the post-cache speed, where it’s writing to the native TLC flash at a respectable 1.6 GB/s. This doesn’t sound like much given the speed of drives today, but it would be at or above the best Gen 3 drives in this mode while generally having a larger and faster cache.

Samsung’s 990 Pro is in the same boat, providing consistent performance outside the cache but looking slow compared to the steady state speeds we see with other drives. In part, this is due to the flash being used on it, as well as the WD/Sandisk drives. Newer flash has more planes and lower latency, both of which can boost throughput. Some drives, like the Inland Gaming Performance Plus, alternatively have smaller caches, which allow the drive to maintain higher sustained speeds. The same goes for the Legend 960 Max. Speed is also not everything, as not all drives write as smoothly in their post-cache modes. Maintaining responsiveness can help a drive feel spunkier when it hits this slower state.

If we take all of this into consideration, the 850P actually has some interesting applications. You could use this as a NAS drive, for example. Generally, we think the Inland Gaming Performance Plus – or the updated Performance Plus – would be better, as a super large cache leans more towards everyday consumer workloads. However, the 850P is steady enough with still sufficient speed. It would probably provide a better experience than the T500, especially as it has twice the flash channels, so it can manage better at high capacity. So, yes, this is a PS5 drive, but its heatsink and performance profile are such that you could use it as a workhorse drive as well.

Power Consumption and Temperature

We use the Quarch HD Programmable Power Module to gain a deeper understanding of power characteristics. Idle power consumption is an important aspect to consider, especially if you're looking for a laptop upgrade, as even the best ultrabooks can have mediocre stock storage in terms of capacity and performance. Desktops are often more performance-oriented with less support for power-saving features, so we show the worst-case for idle.

Some SSDs can consume watts of power at idle while better-suited ones sip just milliwatts. Average workload power consumption and max consumption are two other aspects of power consumption, but performance-per-watt, or efficiency, is more important. A drive might consume more power during any given workload, but accomplishing a task faster allows the drive to drop into an idle state more quickly, ultimately saving energy.

For temperature recording, we currently poll the drive’s primary composite sensor during testing with a ~22°C ambient. Our testing is rigorous enough to heat the drive to a realistic ceiling temperature, but real-world temperatures will vary due to the environment and workload factors.

The 850P has a heatsink, so it’s not going into a laptop, and concerns about power consumption are a little less important. The presence of the heatsink also helps keep the drive cool, so throttling is also not a big concern. Still, you could choose to remove the heatsink, and maybe you want to toss this into a small form factor media machine. In those cases, the 850P’s efficiency – which lands in the lower half of the pack – is sufficient but not great. It’s better than the SM2264-based Legend 960 Max and E18-based Gaming Performance Plus, which are good baselines, but falls behind newer drives and technology.

Our feeling here is that a high-end Gen 4 drive should get at least 400 MB/s per watt, which is generally the case. DRAM-less options can target much higher and are often a better choice if you’re worried about heat or power consumption. If you are going for a high-end drive, ideally you have a heatsink. The one the 850P comes with is very effective, with us measuring a maximum temperature of 54 degrees Celsius. This is very far off from throttling and, frankly, it is a fantastic result.

Test Bench and Testing Notes

We use an Alder Lake platform with most background applications such as indexing, Windows updates, and antivirus disabled in the OS to reduce run-to-run variability. Each SSD is prefilled to 50% capacity and tested as a secondary device. Unless noted, we use active cooling for all SSDs.

Sandisk Optimus GX Pro 850P Bottom Line

The Sandisk Optimus GX Pro 850P brings no real surprises. If you were expecting it to be a WD Black SN850P – which itself is just a Black SN850X with a PS5-compliant heatsink – with a Sandisk badge, then you won’t be disappointed. Technically, there are some firmware optimizations possible for a drive destined to be used in PS5s, but we’ve found that any such changes have little impact on overall performance. The 850P is a drive with mature hardware and firmware, and that’s the main story here. It’s a reliable, consistent, well-performing drive that will rock the PS5 but is also good in regular computers.

Our biggest complaint is probably that the 850P can be bested by other drives in any given category. There are less expensive drives with similar performance in the PS5. There are drives that will be better in a laptop, even assuming the 850P’s heatsink is removed. There are even drives that beat it on the desktop in some areas, or are less expensive. Frankly, it feels like a premium drive, and that’s long been the case for the Black SN850X and its progeny. This is also true of the Samsung 990 Pro, its direct competitor, and there’s nothing wrong with that. If you want a rock-solid drive that can do anything, look no further. If you have a specific application in mind or want to save some money, there are other options.

Considering how much people value their data and worry about storage stability, we think the Optimus GX Pro 850P does have a place. It’s a no-nonsense drive that gets the job done with a proven track record. The heatsink is very effective, and the drive itself doesn’t really struggle with any one workload. While it is designed for the PS5, it would be plenty happy in an enthusiast’s desktop. Not everybody needs a Gen 5 powerhouse. We recommend it for the discerning buyer who wants something fast and reliable without having to guess what hardware is inside some generic brand’s drive.

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A court in Germany has granted court injunctions against Micron, marking a win for YMTC on the European/German front in the 3-year legal war between the two companies over memory technology patents.

According to a Digitimes report, the court ruled on Sept. 18 that Micron did infringe YMTC’s 3D NAND technology patents in two instances. The injunctions could restrict Micron’s supply in Germany and impact the broader European NAND market. Micron said it disagreed with the court ruling and has already filed an appeal. It is also challenging the validity of the related patents in separate legal cases across various countries.

YMTC filed the lawsuit that won the recent injunctions in late 2025 at the Munich 1 Regional Court, opening five cases involving four German utility models and a European patent. The court granted injunctions on two of the utility models with 10-year protection periods — DE202020006166U1 (case No. 7O12615/25) and DE202021004551U1 (case No. 12614/25) — and adjourned the others. The injunctions are only first-instance rulings and can be suspended if Micron successfully appeals at the Munich Higher Regional Court.

The ruling is the latest development in a years-long dispute between the two memory makers that started in 2023 when YMTC sued Micron in California, alleging violations of eight 3D NAND architecture patents. The dispute has since snowballed into a multi-front war involving over 20 patents, with suits and countersuits on both sides. The cases cover patent infringement, declaratory judgment, spyware, libel, false advertising, and invalidation actions, and have been filed in courts across China, the U.S., the U.K., Germany, and in other parts of Europe.

Micron has vehemently denied any wrongdoing and has filed multiple patent invalidation challenges since 2024, the first of which came after YMTC dragged the company to court in China over related issues. Seven of the disputed patents have already been declared invalid, and Micron has said it will continue pushing to safeguard its intellectual property.

3D NAND is a flash-memory storage technology that stores data in products ranging from smartphones and SSDs to enterprise storage systems. Unlike older planar NAND, where memory cells are arranged side by side on a flat surface, 3D NAND stacks cells vertically in multiple layers, allowing manufacturers to pack more storage into a given area while increasing density and lowering cost per bit. Modern NAND chips can contain hundreds of these layers, making the architecture and manufacturing techniques behind them commercially valuable intellectual property.

The Micron-YMTC fight is playing out against the backdrop of the much larger technology dispute between the U.S. and China. Washington has tightened restrictions on China's access to advanced semiconductor manufacturing equipment and other chip technologies, while Beijing has placed export restrictions on many critical raw materials.

The flash shortage has driven up prices for nearly all consumer storage devices. Fortunately, for a limited time, Nintendo Switch 2 owners have a rare opportunity to secure a high-performance Samsung P9 512GB microSD Express card for just $99.99, the original MSRP before the shortage began. Amazon’s $50 checkout discount makes this deal even more enticing, since the microSD Express card typically retails for $149.99.

• Check out the Samsung P9 512GB deal on Amazon

The Samsung P9, one of the best microSD Express cards available, offers blazing-fast sequential read speeds of up to 800 MB/s. That performance is enough to ensure games on your Switch 2 load quickly, and gameplay stays smooth. Samsung does not explicitly state the sequential write speed; however, microSD Express cards in the 512GB class generally offer sustained write speeds of up to 300 MB/s.

High write speeds mean faster data transfers and game installations. Still, 300 MB/s is more than enough for most Switch 2 owners to install large games and updates with little waiting time. In normal usage, the Switch 2 reads more data than it writes, so high read speeds are always a plus.

The Samsung P9 512GB is an incredible steal at $99.99, especially since Amazon typically lists it for $149.99. In fact, $99.99 is the lowest price this card has reached in the past three months, and it's a rare event given the ongoing flash shortage. Even Samsung’s own website currently sells this exact card for a staggering $199.99, making Amazon’s current offer stand out even more.

Deals like this are few and far between, especially for a microSD Express card of this caliber and capacity. If you are running out of space on your Switch 2 or want to prepare for the wave of incoming AAA titles, the Samsung P9 512GB is a smart investment since you are paying 20 cents per GB, the lowest price available right now. Act fast before it's gone.

Enterprise SSD brand DapuStor revealed a new dual-mode configuration for its J5060 enterprise drive that combines SLC (single-level cell) and QLC (quad-level cell) flash on a single drive. The drive’s new firmware runs “selected QLC cells” in a faster pseudo-SLC (pSLC) mode, trading capacity for speed.

As an example, the 30.72TB model trades around 4TB of QLC for 800GB of pSLC, a ratio closer to 5:1 than 4:1. The other two configurations put aside 400GB or 1.2TB with a cost between 6% and 20% of the QLC capacity. “No dedicated SLC NAND is required,” as this uses a “software-defined media configuration,” DapuStor said. Announced last month during FMS 2026, the drive still lacks pricing, a named customer, and a general availability date.

Typical consumer QLC drives have a pSLC cache that fills with super-fast performance, with the data later transferring over to QLC. However, this pSLC mode is dynamic and variable in size. DapuStor’s implementation uses a fixed region sized by the operator, and the regions are exposed as individual block devices to the host. The J5060 is also higher capacity, from 15.36 to 122.88TB, and in the U.2 form factor for PCIe 4.0 x4. Endurance is rated at 0.5 DWPD (Drive Writes Per Day) over five years. The stock 30.72TB model is rated at 30,000 random-write IOPS at 16KB. Its write latency is 35 microseconds.

The capacity trade-off improves what QLC is worse at, random writes, by more than seven times, DapuStor said. It also says average 4K random-write latency is below 8 microseconds. The pSLC has over 25 times the program/erase cycles of the QLC region, although without region-specific DWPD or TBW numbers. DapuStor achieves this with three firmware changes: die-level isolation, optimized SLC reserve allocation, and region-aware I/O scheduling. The high-performance region targets workloads that benefit, namely “database journals, write-ahead logs (WALs), and metadata caches.” The idea is that this drive configuration precludes the need for specialized SLC drives where failure could be an issue; however, you still end up with a dead dual-mode drive on a failure.

The NVMe specification has defined this arrangement since 2019, with an NVM Express presentation at FMS 2019 claiming the goal was to “enable one SKU to be configured by customer for their use case.” An FMS 2019 example showed that some media units run as a small fast region, while the rest run at full density. A prior drive with the same idea, via a Phison firmware split and a host driver, was the consumer Enmotus/Phison FuzeDrive P200 with our 2021 verdict stating that “excessive pricing isn’t for everyone.” Enmotus wound down the same year. It’s also possible to mod a QLC drive to SLC, as we covered in 2024. The difference here is that DapuStor hands the host a second and separate block device with storage software control.

Competitors have other solutions. Sandisk’s bet is on Direct Write QLC on its UltraQLC platform, “which eliminates SLC buffering by enabling power-loss safe writes on the first pass,” Sandisk said, but there are still performance differences, according to our own reporting. Alternatively, Micron’s solution offers a separate cache drive in its XTR. The drive uses 176-layer TLC entirely in SLC mode and is rated at up to 35 DWPD. The drive acts as an optional write buffer for arrays of Micron’s 6000-series SSDs. For reference, Micron rates the XTR at 15 microseconds for QD1 writes.

Product promises are valuable, but any full comparison requires seeing the drives in actual use. Questions remain specifically regarding DapuStor’s drive, as pSLC region specifications are lacking. It is uncertain what commands the drive employs and whether the region split is modifiable live; usability depends much on the undemonstrated storage software. More details for the QLC-based, PCIe 5.0 sibling R6060 would be nice, too. Utilizing multi-bit flash in a single-bit, SLC mode for performance or endurance reasons is not a new idea, but balancing those with the increasing need for capacity remains a challenge.

Apple’s latest iPhone 18 Pro series went on sale last week, and the company’s decision to use QLC-based NAND for higher-capacity storage variants appears to come with a trade-off. Bilibili channel Homolab recently tested a 1TB iPhone 18 Pro Max and found that its storage performance can drop significantly under sustained heavy workloads. Since QLC stores four bits of data per memory cell when compared to three bits with TLC, it allows manufacturers to offer higher capacities using the same physical space. However, this higher storage density comes at the cost of slower performance, particularly when handling large amounts of data.

Homolab compared the 1TB QLC-based iPhone 18 Pro Max with a 512GB TLC-based iPhone 18 Pro. While both storage types perform fairly similarly in 4K read tests, the QLC model falls behind by 38% in a low-queue-depth mixed workload, scoring 8,168 compared to 11,285 for the TLC model. Under heavier workloads, the gap narrows, although the TLC storage model still maintains a 12% advantage.

The drop in performance is even more apparent when it comes to sustained write tests. The iPhone 18 Pro Max uses a fast SLC cache that can deliver speeds of up to 3,000 MB/s. Once that cache is exhausted, a secondary TLC-based buffer takes over, averaging around 578 MB/s. When both cache buffers are exhausted, the phone has to write directly to the underlying QLC NAND. At that point, sustained write performance can fall to 79.4 MB/s, with speeds occasionally dropping as low as 25.6 MB/s.

That is significantly slow and comparable to the performance of many budget microSD cards (microSD Express cards are much faster). Things look even worse once the storage starts filling up. At 60% capacity, the available SLC cache drops from 250GB to just 58GB. This also causes the secondary buffer to slow down to 396 MB/s, while direct QLC writes average just 45 MB/s and occasionally fall to as low as 1.1 MB/s.

It’s important to note that these are synthetic benchmarks and are meant to represent a worse case scenario. Users should not experience any performance issues during typical tasks such as web browsing, messaging, gaming, or taking photos. Any slowdown is likely to be noticeable only during specific workloads, such as 4K or ProRes recording, large file transfers, or data backup restores. Having said that, testing by Homolab does point to the trade-off involved in using QLC NAND for a high-capacity flagship smartphone, particularly for users who regularly deal with storage-intensive tasks.

A new report claims Chinese DRAM champion CXMT is eyeing production of 3D NAND memory. Reuters reports, citing three people familiar with the company's plans, that CXMT intends to build a 3D NAND R&D production line at its second manufacturing facility near Beijing. There is no information on when the experimental production line will become operational, though, given that CXMT's second Beijing fab has not even broken ground yet, the line is at least two or three years away. In addition, the memory maker has established a research institute in Beijing that has NAND flash development among its projects, according to one source. CXMT has not formally confirmed any 3D NAND initiatives, so the information should be taken with a grain of salt.

For now, there are no details on CXMT's 3D NAND architecture, number of active layers, process technology, expected performance, or production capacity. Nevertheless, the report claims that CXMT has already discussed its NAND ambitions with prospective customers. One of them is said to be a recently established company that plans to use CXMT-made NAND devices in storage products aimed at AI and supercomputing applications.

It remains to be seen whether CXMT's 3D NAND project will eventually progress to high-volume manufacturing, but if it does, the initiative will take CXMT beyond its traditional DRAM specialization and directly into YMTC's territory. Until recently, China's two major memory producers had focused exclusively on their 3D NAND and DRAM realms where they have achieved quite a success. Yet, it looks like both companies want to become one-stop shops for DRAM and NAND — just like their bigger rivals Micron, Samsung, and SK hynix — as YMTC is reportedly exploring DRAM production.

While CXMT's alleged plan to build 3D NAND may look somewhat logical from business diversification point of view, it does not make a lot of commercial sense for now.

Or China's industrial policy?

CXMT is China's dominant DRAM producer and posted $22.41 billion in revenue and $11.57 billion in net profit in the first half of the year after years of bleeding money. Despite obvious success, the company is still considerably smaller than the Big Three memory suppliers, which means it has plenty of room to expand in the industry where it already has experience, process technology, fabs, and customers. Furthermore, AI gives CXMT an obvious reason to focus resources on advanced DRAM as well as HBM3E, which are arguably much more strategically valuable products than commodity 3D NAND.

That said, for CXMT, allocating resources to 3D NAND, which requires completely different process technologies, manufacturing expertise, and equipment, does not make much economic sense. However, from the Chinese government's perspective, turning CXMT into the country's second major 3D NAND producer fits almost perfectly within its semiconductor self-sufficiency plans.

CXMT was created with Hefei government money (which held a 37% stake in the company during its IPO) and received support from China's Big Fund, which means that federal and local governments retain control over the company and may shape its strategic decisions, which is exactly what they do. Whether or not CXMT can indeed become a decent 3D NAND maker is an entirely different question.