Just like we suspected, our fellow Australian hardware examiner TrashBench is up to shenanigans again. Not too long ago, after putting a graphics card in the "wrong" place for much better cooling results, he's ... thinking bigger, let's put it that way. He took an old 4-kW outdoor radiator-fan unit from a split air-conditioning setup (sans gas) and hooked it up to a water-cooling loop to assess its performance.

He kicked off the video with his best impression of Crocodile Dundee, and set out to rearrange the unit for the task at hand, as he only needed the actual radiator, fan, and pump. Most of the fiddly guts were taken out, and casters were added for convenience. TrashBench then added a bog-standard reservoir to the main enclosure.

Moving on to the PC side, he converted a T-joint into a Y-joint with judicious application of heat and force, and, being the ever-clever craftsman, designed 3D-printed mounting brackets for the various cold plates. It was around this time that it was made certain he'd be successful, as at 02:49 you can see that his knuckles paid the requisite blood toll to the machine god.

After firing up the entire system, he set to benchmarking, enlisting both a modern RTX 5060 and a hotter, earlier RTX 3080 for the process. The 5060 is a very power-efficient GPU, and its temperature with the standard cooler was a tame 52ºC. However, the mighty power of four kilowatts' worth of cooling brought that down to just 33ºC, around the temperature of lukewarm water, and a 16ºC drop altogether.

With such a wide thermal range to work with, he set out to overclock the living daylights out of the GPU, moving the boost clock needle from 2902 MHz up to 3300 MHz. Despite the 14% clock-speed improvement, average FPS saw a mere 3% uplift, clearly highlighting how perfectly Nvidia has the power/performance curve dialed in since the RTX 2000 series.

He then moved on to the RTX 3080, a beastly, much more power-hungry card that could provide a worthy challenger for the Fujitsu radiator. It was promptly defeated, and its temperature went from 65ºC down to just 28ºC, or in other words, not much above ambient. Overclocking this card, however, also yielded a mere 3% fps, barely worth the man's time.

The final challenge was seeing how well the teeny weeny Fujitsu could handle a combined GPU and CPU load. The processor on hand was probably the worst possible consumer chip to try and keep cool, the lightning-fast and flame-hot Intel Core i9 14900K.

TrashBench hooked it up and saw CPU temperatures drop 18ºC down to 76ºC, a strong achievement for this silicon outside of rooms with liquid nitrogen buckets. As for the graphics card, its heat sensor simply didn't move at all, suggesting that the radiator had far greater headroom than TrashBench had hardware.

YouTuber hardware enthusiast and Thermal Grizzly boss der8auer tested a two-year-old liquid metal thermal interface material (TIM) application with an electron microscope in his new video, discovering that it doesn’t dry out. Instead, the gallium bonds with the copper in a reaction to form a solid compound. On copper, that layer’s heat conduction performance is about one-quarter of the bare metal’s, and nickel plating keeps it about 10 times thinner.

His test showed the TIM as liquid after one hour, no liquid visible with crystals everywhere at the two-month mark, and then unchanged after two years. “After a total of two years, this honestly did not change further,” he said. The test relied on storing the setup in a vacuum or a nitrogen-filled box between sessions to avoid oxidation.

The TIM in question is an alloy of gallium and indium, often including tin, which is liquid at room temperature (Thermal Grizzly sells its own as Conductonaut); gallium melts at about 30 degrees Celsius, with the gallium-indium-tin mix melting at only 11 degrees. Improving cooling at the interface bottleneck is becoming a real issue as heat per surface area continues to rise. His examples are the RTX 5090 and RTX 5080, which he says have “twice” and “three times” the power density of the 8800 GTX.

How the liquid metal reacts depends on the cooler material. With aluminum, the gallium travels along the grain boundaries once the oxide layer is broken, and this weakens the metal. His demo on a scrap 2 mm aluminum sheet showed surface swelling after about five minutes, and it became brittle within half an hour. This reaction has been “common knowledge for a very long time.”

With copper, the liquid metal on the cold plate of Thermal Grizzly’s new stainless steel water block can’t be wiped off with isopropyl alcohol or acetone after less than five minutes. The gallium bonds with copper to form CuGa2, one copper atom to two gallium atoms, with the leftover indium and tin forming other solid areas. This makes the film look like it is solidifying. CuGa2’s heat conductivity is rated at about 100 W/mK versus copper’s roughly 400. Since CuGa2 stays solid up to about 254 degrees Celsius, “you will not be able to melt it again.”

The layer grows about 1 micrometer a day until it reaches about 50 to 100 micrometers, depending on temperature and how much gallium is available; his example of pure gallium between copper plates at 70 degrees Celsius shows about 4 micrometers over 96 hours. The liquid metal “doesn’t really dry out”; it “reacted chemically and it formed a solid compound,” so the metal is still there in another form.

On nickel-plated coolers, the gallium forms NiGa5 instead, one nickel atom to five gallium atoms, which is also solid at room temperature. The nickel plating stops the layer at about 10 times thinner, at 1 to 5 micrometers, or 5 to 10 micrometers on his slide, but NiGa5 conducts heat worse than the copper-gallium compound. However, nickel is “most of the time superior” in his estimation because much less gallium gets absorbed into the surface, and it protects the copper underneath.

Removing the residue is tricky, and he recommends Thermal Grizzly’s TG Metal Polish & Restore, with a chemical that lowers gallium’s surface tension. The company’s Sept. 30 blog post describes it as a surfactant that binds gallium to stop it from re-sticking. It costs $22.11 direct for 30 g of paste, a polishing pen, and microfiber cloths. His demo showed fresh film coming off bare copper. A PC Games Hardware forum user used it to clean an Aqua Computer block that had run liquid metal on a delidded Skylake-X since 2018, with removal taking about an hour.

This isn’t a TIM for the average user, and he recommends that it should “stay in the enthusiast bubble,” intended for very high power density components like a manually overclocked CPU. Thermal Grizzly aims to replace nickel with new coatings, “hopefully next year.” It also plans to release a new version of its KryoSheet graphene pad for bare dies shortly, which he says is maybe three or four degrees worse than liquid metal but worth a try, “especially if you look at the pricing.”

For cost, he points out that his company pays almost 10 times as much for gallium after five years, from €300 per kilogram to €2,500–3,000. Prices have more than doubled since the start of 2025. China supplies 99% of the world’s gallium, and its ban on gallium exports to the U.S. is suspended only until Nov. 27, 2026, with export licenses still required.

Frore Systems has introduced its bespoke LiquidJet Diamond liquid-cooling coldplate series that uses a diamond surface combined with a multi-stage 3D short-loop jet-channel microstructure to address precise hotspots on next-generation AI accelerators, such as AMD's Instinct MI400 and MI500-series, Nvidia's Rubin, and beyond. The company claims its new coldplates can handle hotspots with power densities reaching 770 W/cm², reduce GPU temperatures by up to 22C compared with conventional coldplates, and improve AI token throughput per watt by as much as 35%.

LiquidJet Diamond combines the expertise it used for its original LiquidJet coldplate product and the LiquidJet Nexus bespoke coldplate for Nvidia Blackwell and Nvidia Rubin-based servers. Unlike Nexus, which integrates multiple coldplates into a large cooling assembly for several processors, LiquidJet Diamond is an individual GPU coldplate, albeit a bespoke one.

From an internal technology perspective, Frore’s coldplates employ a three-dimensional, ultra-short-loop, multi-stage architecture with coolant channels customized for the power distribution of a specific processor. Meanwhile, the key innovation in LiquidJet Diamond is an additional heat spreader integrated into the bottom of the coldplate. This spreader incorporates diamond wafers positioned directly above the GPU’s hotspots to distribute heat more efficiently before it reaches the liquid-cooling structure. Diamond (carbon) has exceptionally high thermal conductivity, which can exceed 20 W/cm·K, compared with approximately 4 W/cm·K for copper. According to Frore, the addition of diamond heat spreaders allows LiquidJet Diamond to handle hotspots with power densities of up to 770 W/cm², compared with approximately 600 W/cm² for the original LiquidJet. However, the company has not disclosed how the diamond wafers are manufactured or integrated into the coldplate.

According to Frore, its original LiquidJet coldplate reduces GPU temperatures by approximately 12C compared with conventional skived coldplates (based on its simulation model), which translates into a 25% improvement in AI tokens per watt, according to the company’s estimates. Meanwhile, a custom Liquid Diamond heatspreader promises to further reduce hotspot temperatures by up to 10°C, while the complete LiquidJet Diamond solution provides a 16C – 22C reduction in GPU temperatures and improves token efficiency by 30%–35%, Frore claims. The company also expects 75% higher heat-transfer efficiency and over 150% higher maximum hotspot power density than conventional cold plates based on its models.

Frore plans to demonstrate LiquidJet Diamond at the OCP Global Summit on October 12 – 16, where it will showcase cooling for Nvidia's 2,300W Rubin accelerator and hotspots reaching 770 W/cm². However, the company has not disclosed whether the demonstration involves production GPUs or some type of thermal test vehicle.

YouTube hardcore PC modder TrashBench attached waterblocks, a water pump, and a 360mm radiator to a Metabox laptop with an Nvidia GTX 1060 and Intel Core i7-8750H. This Frankenstein’s monster of a laptop dropped a whole 60℃ on both the CPU and GPU during benchmarks and stress tests and gained an average of 14% after overclocking.

TrashBench, a YouTuber popular for extreme PC modifications involving various watercooling solutions, decided to “fix” laptop cooling by taking a cut-up 360mm AIO from another project and plans to use it on the Metabox P950EP. Metabox is an Australian brand of laptops rebranded from Clevo, an ODM brand from Taiwan that often gets rebranded in various countries. TrashBench intends to use this laptop for his daughter to play Fortnite on.

The modder intended to use the stock AIO pump along with a second waterblock for the CPU, but after testing whether it would be strong enough to push through a second block, TrashBench realized he would need a bigger pump. He also needed to use another waterblock since the new pump was a standalone one, unlike the waterblock and pump combo on an AIO.

The waterblocks were mounted via a 3D-printed holder, then screwed down to the existing holes previously used for the stock heatpipe and blower cooler. More 3D-printed mounts were used to hold the radiator behind the screen of the laptop, but couldn’t be screwed in because the space between the screen and shell was too small. TrashBench reluctantly used Loctite 2-part epoxy to attach the radiator mount onto the laptop.

That’s not all epoxy was used for, as he didn’t forget about the RAM and VRMs. A heatsink was attached to them, with thermal pads bringing the RAM level with the VRMs to use a single heatsink for each cluster. The VRMs had a dab of thermal paste and a spot of epoxy to keep the heatsink in place, making the modification permanent.

After fully assembling everything and attaching the blocks, pump, and radiator with flexible clear tubes using screw hose clamps, TrashBench tested it for leaks. “I think we’re good,” he says, just before a few bubbles passed by.

The laptop uses 19v, while the pump and fans use 12v, so a DC-DC step-down converter was soldered to the original blower fan’s electrical contacts. Unfortunately, the power source powers on as soon as the laptop is turned on, with no way to make them only turn on under load. So the modder used a toggle switch mounted to a 3D-printed plate, screwed onto the bottom shell that had a large gaping hole cut out of it to accommodate the pump and waterblocks.

To allow the laptop to stand, a 3D-printed riser was screwed to the bottom and is the final touch to the build. As ridiculous as it looks, it impresses with its performance, averaging 60℃ below stock, with the CPU and GPU staying well below 40℃ under full load.

Conservative but clear performance gains were seen after benchmarks, but with the amount of temperature overhead, TrashBench decided to see how much more he could get by overclocking, and it was worth it, as Forza Horizon 5 went from 75 FPS to 77, and then to 83 FPS after overclocking.

Tech enthusiast and developer Matt Birchler has tested an Apple iPhone 18 Pro with a can of La Croix used as a cooling device to address persistent thermal throttling that he noticed during his other tests with the phone. Surprisingly, this yielded much stronger results than one would assume, given that he simply placed the can of sparkling water on top of the phone, providing a 25% improvement in sustained performance.

Birchier has been benchmarking the A20 Pro processor inside the iPhone 18 Pro, and it has so far offered excellent transcription results in its normal non-sparkling-water-cooled configuration. In one test run, the latest Apple smartphone hit a maximum speed of 447.9 words per second, before settling down to a little over 320 for the 7th to the 20th runs. The reduced performance during the latter stages of a prolonged benchmark run is normal for nearly every portable device, as they reduce performance to avoid thermally damaging their chips and other components.

It’s exactly for this reason that high-performance computers often come with the best CPU coolers, with some enthusiasts preferring the best AIO coolers or custom water-cooling loops to get the most out of their high-end processors. However, this usually isn’t possible with most mainstream phones, unless you’re running a specialized gaming handset like the liquid-cooled Redmagic 11 Pro — but it seems that Birchler found a solution for the iPhone 18 Pro. “I did some benchmarking today and saw how the newest iPhone thermal throttles, which isn’t severe, but does happen,” the developer said. “I know from experience that if you put a cold beverage on the back of your phone, it will cool down really quick, so I thought…the test is obvious.”

So, Birchler pulled out an ice-cold can of La Croix from the fridge, started a benchmarking session consisting of 20 runs, and placed the drink on the back of the phone. After the tests were completed, the results were as expected: even though its initial run had a slightly lower result of 429.5 words per second, the “liquid-cooled” iPhone 18 Pro had a higher average of 400.4. This meant that giving the iPhone a cold drink helped it sustain around 25% higher performance, but at the cost of keeping the phone facing down while running heavy loads.

The average user wouldn’t need cooling solutions like these for most mobile devices. But if you use your device for extensive loads, like gaming or shooting and editing photos and videos, you might notice slower performance and a dimmer screen after a few minutes. You could follow Birchler’s lead and strap a cold drink to the back of your phone to reduce thermal throttling, but it’s going to be inconvenient and impractical. After all, it’s quite awkward to hold your phone while a can is sticking out of its back. This is why some smartphone accessory manufacturers make devices like the Black Shark Magnetic Phone Cooler 6 Pro for gamers or the SmallRig Universal Hyper Chill Cooling Phone Cage and the Tilta Khronos Advanced Kit for filmmakers.

Other enthusiasts have also experimented with their own designs, like this monstrous SSD cooling solution strapped to the back of an iPhone 17 Pro Max. These will allow you to squeeze more performance from your phone, but at the expense of an impractical design, additional weight, and shorter battery life.

Noctua is teaming up with Forced Physics DCT to explore whether the company’s JouleForce micro-channel array-based cooling can be adapted for desktop PCs and workstations. The long–term partnership will focus on developing a quieter way to use the tech, although Noctua said in its announcement that the partnership is not tied to any specific product or release date.

Claimed to be a new third path to cooling, JouleForce goes beyond traditional air and liquid cooling methods. While it is still based on air-cooling, its capabilities far exceed today’s modern CPU coolers, with the ability to cool over 2000W of thermal energy. The technology uses densely packed micro-channels designed to improve heat transfer. According to Forced Physics, its geometry prevents the boundary layer that normally forms along cooling surfaces, allowing heat to be extracted along the entire length of each channel. This essentially enables large amounts of heat to be removed using air alone, without requiring a liquid-cooling loop.

While that sounds impressive, bringing the technology to desktop PCs comes with a major challenge. The micro-channel arrays currently have a pressure drop that is “an order of magnitude and more” above the range of conventional PC fans. Thus, in its current state, JouleForce relies on industrial blowers, high-speed centrifugal fans, or even vacuum pumps to push air through the arrays.

Noctua’s expertise could prove useful as the company is known for developing some of the best performing PC fans. The partnership will investigate ways to reduce the pressure required by the micro-channel arrays or generate the necessary static pressure without making desktop systems excessively loud. “The pressure levels this technology requires in today’s implementations are currently supplied by equipment nobody would want on or under their desk, so this is a demanding, long-term engineering task – and one that we are eager to tackle,” said Roland Mossig, CEO at Noctua.

For now, Noctua and Forced Physics are still in the early research stage, with both companies planning to share updates as the project reaches significant milestones. If the two companies can crack the airflow and acoustic challenges, JouleForce could eventually make its way to desktop PCs. At the same time, Noctua would have a serious advantage in the market compared to other heatsink manufacturers.

A premium PC DIY fan brand has announced that one of its prized spinners is being used in a 4K camera. Noctua says that its NF-A4x10 5V PWM was used by the CAIM1 camera designers due to its quiet, compact nature and strong airflow and pressure performance. This camera runs two intensive processing tasks simultaneously within a compact shell, high-bitrate imaging and cryptography, hence the need for active cooling to prevent throttling.

The CAIM1 is something of a niche product. It has been designed to create photo and video captures that one can say with certainty haven’t been altered or generated using AI. Noctua says it is “cooling a camera built to prove reality.” CAIM1 is short for Counter Artificial Intelligence Machine 1.

From the brief description provided by the source, this anti-AI functionality seems to work by piping the imagery directly from the lens/sensor through an “onboard hardware attestation with edge cryptographic proof generation” process. This is stored on the camera’s “immutable, decentralized storage, enabling the origin of the media to be verified independently,” says the Austrian air-cooling specialist.

Of course Noctua’s involvement was beneficial to the camera makers for its high-quality precision fans. The CAIM1 generates heat through its high-bitrate 4K imaging activity, its cryptographic processing, all within the confines of a compact handling-friendly shell. Other key considerations of the designers were precise PWM fan control, and finding a fan with minimal noise (as the camera records audio) and minimal microvibrations.

Noctua says its NF-A4x10 5V, with its PWM’s SSO2 bearing system and smooth motor drive fitted the bill. This tiny fan was leveraged in a unified single-airstream cooling design with custom anti-vibration mounts, situated right behind the image sensor. This directs air across the sensor’s alloy heatsink backplate, and which gets exhausted though the camera chassis left side.

Our nozzle-headed readers will also be pondering over the Prusa branding on the camera body. The simple answer is that the CAIM1 is still at the prototyping stage and these models have been prepared using 3D printers and Prusament PETG Noctua Beige and Noctua Brown for the outer shell and fan mount. CAIM1 devices will be showcased at a handful of trade shows in Japan later this month. However, commercial batches are targeting Q1 2027 availability.

Today we’re testing MSI’s latest flagship AIO, the MEG Coreliquid E15 360, a luxury AIO with a premium black-and-gold aesthetic symbolizing authority and elegance. So we’re expecting market-leading thermal performance. Of course, the feature that stands out the most is the stunning 6.67-inch curved 2240x1080 AMOLED screen. The whole design looks and feels premium, with a price tag to match.

Let's take a look at the specifications and features of this CPU cooler, then we’ll go over thermal and noise benchmarks to decide if the MEG CoreLiquid E15 360 is good enough to make our list of the best CPU coolers on the market.

Cooler specifications

Features of MSI’s MEG CoreLiquid E15 360 AIO

▶️ Premium black-and-gold aesthetic

MSI’s MEG CoreLiquid E15 features a design that just oozes a feeling of premium quality – each component is precision-made using high-quality components, with gold colored plating flanking black metal. The highlight of this cooler, of course, is the premium curved screen, but if, for some reason, you’d prefer not to use the screen, a stylish black-and-gold pump cover is also included.

▶️ RAM Clearance

As with most AIOs on the market, MSI’s E15 doesn’t overhang or interfere with RAM DIMMs at all, allowing for compatibility with all sizes of DDR4 or DDR5 DIMMs, no matter how tall.

▶️ Magnetic Penrose Triangle

A pretty nifty piece of swag included with this AIO is a magnetic Penrose triangle and, boy, let me tell you, this magnet is strong! How strong? I threw it across the living room to a metal door and it instantly secured itself to the door!

▶️ 28mm thick single-frame fans

There’s more to a cooler than just the heatsink. The included fans have a direct impact on aesthetics, noise levels, and overall thermal performance. The E15 features a 360mm single-frame fan unit, and it is pre-installed for user convenience, saving a few moments during cooler installation.

▶️ MSI EZ Display software – Pros and Cons

Strictly speaking, you don’t actually need to install MSI’s EZ Display software to enjoy the functionality of the included screen. The E15’s default animation shows a Penrose triangle against a background strongly reminiscent of the brutalist Isu ruins from The Fate of Atlantis DLC in Ubisoft’s Assassin’s Creed: Odyssey.

If you’re happy with this default animation, no software installation is necessary. It’s only if you want to customize the screen that software installation is necessary.

Once the MSI EZ Display software has been installed, there are three primary configuration styles. The first is a “full screen” mode that has several stunning animations, each unique but in the same style as the others.

In addition to the visual theme, you can choose to enable several metrics on the screen. In the image above, I’ve enabled the date and time, but you can opt for other things, like CPU and GPU temperatures, processor frequencies, etc.

These are nice features and certainly look good, but that’s where the customization ends for metrics. The EZ Display doesn’t currently let you change the position or size of the metrics displayed. If MSI wants this AIO to appeal to tech enthusiasts, that’s a feature they’ll need to implement – especially when you consider the E15’s luxury price tag. This lack of proper customization is especially annoying when trying to display metrics with a custom image, as shown below.

Another aspect I would like to see improved is the ability to deselect themes in the “playlist.” Currently, if you let the animations shuffle or loop, every single animation (preset and custom) that you have included in your library is played.

The second configuration mode available for this screen is a “split-screen” option, which currently has only two presets. As the mode’s name implies, this splits the display into two parts, allowing for one animation or image on each side of the display.

The last mode available for this screen is extended mode, which allows you to use the display as a secondary monitor with Windows.

This allows you to use your own software and show off themes and images entirely of your own creation, play movies of any length, etc. There is one downside though: when I tested this mode, HDCP would not work on either the MSI display or my primary LG ultrawide monitor when streaming video from Amazon Prime on my primary monitor, resulting in degraded video quality.

▶️ Packaging

The outer packaging loudly advertises the product, with a stunning black-and-gold theme and the AIO’s image on the front. The individual parts in the package are protected with cardboard, with mini boxes for the radiator, pump, accessories, and etc.

Included with the package are:

• Mounting hardware for AMD and Intel platforms
• 120mm fans
• Thermal paste
• Magnetic Penrose triangle
• Bending tube clips

▶️ MSI MEG CORELIQUID E15 360 AM5 Installation

To begin putting things together, you’ll first need to remove the default AM4/5 retention brackets and replace them with the included mounting bars for the AIO.

Next, take the mounting bars and secure them with the included screws.

Now it’s time to apply the thermal compound. If you’re not sure how to do that, we have a handy thermal paste application guide that covers the different methods you can use.

After thermal paste is applied, take the CPU block and press it against the mounting bars, using the built-in screws to secure it in place.

At this point, you’re mostly good to go. You can leave the AIO set up as above if you want, but most users will want to take off the cover from the CPU block and place the screen on top of it instead.

The final step, of course, is to connect the AIO’s cables – ARGB, USB, and PWM.

Real-world testing configuration – AMD AM5 platform

We’ve tested coolers with both the Ryzen 9950X3D and its non-V-Cache sibling, the 9950X. There are some differences in how the 9950X and 9950X3D CPUs are impacted by thermal events. While the heat output of the CCDs of AMD’s 9950X3D is relatively balanced, the 9950X I used has one CCD that runs much hotter than the other, with a difference of over 10 degrees Celsius in some scenarios, shown below.

We’ve since returned to using a 9950X3D for cooler testing, as it has a more balanced heat profile, and is almost certainly a more widely adopted CPU. The benchmark results shared in these reviews may differ from others because I emphasize results that are comparable to real-world use. This means I generally test CPU coolers inside of a closed desktop case, which increases cooling difficulty compared to other testing methods.

Many reviewers test coolers on open test benches, which have a combination of lower airflow needs and lowered ambient temperatures. This can make weak coolers appear stronger than they really are. Some publications have also used generic thermal plates to test cooling solutions. I reject both of these methods because they don’t accurately reflect real-world cooler conditions.

Our latest testing setup uses the FLOVA F50 computer case from Tryx.

This case features a unique “crossflow” fan that pulls air from the side, which the company claims is more effective than traditional intake fans. For air cooling tests, we’ve added a single Noctua NF-A12 G2 intake fan.

PBO Performance and maximum noise levels

We’re going to start this review’s benchmark section by focusing on a traditional maximum performance test, with the CPU cooler’s fans allowed to reach their fastest speeds, for the best cooling possible.

Turning on PBO allows AMD’s Ryzen 9 9950X3D to stretch its legs and consume over 260W. Enabling PBO allows for high power consumption and heat output. When using MSI’s X870E Carbon Wifi motherboard, the CPU will reach its TJ Max (peak temperature) of 95 degrees C (203 F) and thermally throttle, to some extent, with most coolers. When this throttling occurs, I’ve measured the average power consumption to determine performance.

I’ve highlighted the performance of the MEG CoreLiquid E15, the P22, and the prototype P22 to demonstrate how MSI has been continuously improving the thermal performance of its AIOs. The MEG E15 has the second-best results in our current test bench, averaging 62 degrees Celsius over ambient (84 C). Out of curiosity, I also tested the thermal performance to see how better temperatures might perform with an open case – and surprisingly, there was only a single degree’s difference.

The maximum noise levels of this cooler are on the louder end, measuring 48 dBA. But to my ears at least, the the pitch of the cooler’s fans is soft, which makes the cooler feel quieter than how it measures.

200W thermal benchmarks

For the next thermal test, I leave the motherboard settings at their defaults, which results in a power limit of 200W when running Cinebench R23.

Thermal results in this scenario were similar to our first test, with MSI’s E15 being a top performer, holding the third-best results, averaging 47.1 C over ambient (69.1 C).

150W + GPU thermal results

Our next test runs Cinebench on the CPU with a 150W power limit, while also running Furmark on MSI’s RTX 4070 Ti Super Ventus 3x OC. This causes the GPU to consume ~295W of power. This test is designed to emulate the thermals of games, which stress both the CPU and GPU.

MSI’s E15 AIO once again performs well here, with our second-place result when testing in our Tryx FLOVA F50 test bench. Out of curiosity, I also tested this AIO in an open case, which resulted in an additional thermal improvement of 1.8 C.

Noise levels in this scenario were moderate, registering at 40.9 dBA with our Pyle PSP25 sound meter.

Noise-normalized testing

Most testing is performed with the cooler tied to the default fan curve of our MSI X870E Carbon motherboard, but some of y’all prefer to see tests when the noise levels of coolers are equalized. This is especially important to those of you who prefer silent computers. This next test has the CPU cooler noise-normalized to 38.9 dBA, with PBO enabled for the Ryzen 9 9950X3D CPU.

This test is especially difficult, because in addition to the reduced noise from the CPU cooler, our current test bench’s system fans are configured to run extremely silently, below the floor of the noise meter I use to measure dBA.

The results here are simply excellent. MSI’s E15 is one of the few AIOs on the market capable of keeping the CPU under TJ Max with PBO enabled in our current test bench, even when the noise levels of the fans are limited.

Karhu DDR5 RAM thermals testing

Your CPU cooler does not operate in isolation. It has an impact on not just your CPU’s temperatures, but also the other components in your build, like your RAM and GPU. To that end, I’ve run the Karhu RAM stress test. This places a load of ~153W on the CPU and ensures system RAM (DDR5 in my case) is fully stable. In this type of scenario, most AIOs tend to produce worse results than air coolers.

DDR5 temperatures in this test were good, the best of any AIO, save those incorporating VRM or RAM fans.

Conclusion

With a hefty $399 price, this AIO is strictly for users who don’t care much about build budgets. The stunning black-and-gold aesthetic reflects that luxury status, and the included 6.7-inch screen and preset animations are stunning. Thermal performance is also among the best AIOs on the market, so the cooler isn’t all about style over substance.

But of course, with the ongoing inflated prices of RAM, storage, and GPUs, most of us aren’t likely to seriously consider spending nearly $400 on a cooler. If you’re looking for a more budget-minded alternative, I’d encourage you to check out Arctic’s Liquid Freezer III Pro instead.

If you can’t have enough RGB and LCD screens inside your PC case, Thermalright just announced another must-have accessory for your build. The Fan Frame Vision-1 is a magnetic clip-on screen that snaps onto most standard 120mm fans on the market. This fan accessory boasts a 3.69-inch IPS display, is available in black or white, and can be mounted horizontally or vertically. Unfortunately, this device isn’t available on Amazon yet, although more “adventurous” enthusiasts could get it off AliExpress for $37.14 apiece, making it more expensive than some of the best PC case fans you can buy today.

Although this accessory mounts in front of your case fans, Thermalright claims it offers enough clearance that it doesn't interfere with airflow. It connects to your PC via a USB 2.0 hub inside your case, although you could also attach it to a blank USB-A port with the included adapter if you’re already out of interfaces on your motherboard. It’s also integrated with Thermalright’s LCD software, TRCC, making it easy to customize what information and theme you see on the screen. Given that TRCC has also already been ported to Linux, you can enjoy this overload of screens on your gaming PC, even if you’ve stepped away from Windows and into SteamOS or other Linux builds designed for gaming.

This accessory pairs well with some of the best AIO coolers that come with their own screens, letting you create a unified theme across all your cooling solutions. Because it has a standardized design, you can mount it on most standard fans that use metal screws at each corner. The magnetic mounts on the Fan Frame Vision-1 would easily grab onto the heads of these screws, keeping the screen secure inside your case. Unfortunately, if you use larger fans, like the Thermalright TL-US24/36, you won’t be able to use this as an add-on, especially if they use offset screws. This means that the magnetic studs on the base of this accessory would have nothing to grab onto.

The Fan Frame Vision-1 and other similar LCD screen accessories won't bring any performance benefits to your PC build. But if you have an overpowered computer, these little extras wouldn’t hurt one bit. Besides, all that eye-candy would help remind you how much you’ve spent on your gaming computer, especially given the egregious prices on RAM and storage these days.

Germany's leading consumer testing organization, Stiftung Warentest, has warned people to avoid fake air conditioners from Epicooler. Golem.de reports that this direct-from-China brand also ships to the U.S., and its so-called air conditioner contains “a simple PC fan combined with a small heating element” [machine translation]. We don’t know the PC fan brand. In tests, the Epicooler didn’t reduce the temperature of the room when set in its ‘Cold Wind’ mode.

Europe has been literally burning this summer, so countless folks have become interested in acquiring an air conditioner, perhaps for the first time. Epicooler reportedly aggressively markets its air conditioners with “AI-generated videos on social media, YouTube, and in online magazines,” notes the source. Moreover, its devices look very much like traditional air conditioners but sell for a fraction of the price. Many people therefore have taken a chance on this ‘bargain’ only to find out they have actually overpaid for a box containing a PC fan alongside a heating coil.

We guess the Epicooler price is just low enough to attract some chancy purchases. The source says this fake aircon is sold for €163, which is about $188. These devices are always shipped from China, it is noted, even when local warehouse stock is advertised. It is thought that this is a method that helps Epicooler swerve national regulators such as the FTC, as well as sidestep local consumer protection laws regarding product description accuracy, refunds, etc. This kind of operation is also easy to ‘dissolve’ and reappear under other brand names once the ‘game is up.’

There have been previous cries of fake, concerning Epicooler products. Its products have been panned on various consumer review sites, criticized on social media, and more. But it is good to get these ‘air conditioners’ fully exposed by a leading consumer testing organization in Europe.

Stiftung Warentest seemed to be suspicious of the Epicooler as soon as it was received. The device weighed less than 3 kg (6.6 pounds), whereas a genuine internal unit might weigh 13 kg (28.7 pounds) and require a 38 kg (83.8 pound) outside unit. A sticker on this device also spoke the truth, reading ‘Wall Mounted Heater.’ So there was no compressor/condenser/expansion/evaporation process going on here to genuinely cool the space where it was installed. It was just a “standard PC fan and a small heating element.” The consumer site also commented that when using the heating element “the device quickly became so hot that we decided to switch it off again.”

The Epicooler is very cheap for an AC unit, which can often cost 10x more. But they’ll work. However, it is expensive for a fan, with the best consumer-reviewed fans (accurately advertised) available for half as much money as an Epicooler, noted Stiftung Warentest.

Please be careful with your cash, and keep in mind the maxim “if something seems too good to be true, it probably is.”

The latest cooler on our test bench is the Sigma L36 Pro, a high-end AIO with a 3.5-inch display from relative cooling newcomer Ocypus. This manufacturer is known for quirky design choices that help set it apart from its many competitors. I found the company’s Iota C70 computer case and A62 digital air cooler especially interesting products when I tested them last year.

Like many other AIOs we’ve reviewed lately, the Sigma L36 Pro features a display – a large 3.5-inch detachable screen in this case, capable of displaying performance metrics and animated images and video.

Screen aside, the technical specifications of the product are impressive. The static pressure exerted by the fans is nearly twice as strong as many competitors – rated for up to 5.8 mmH20. But even more impressive than this is the price of the liquid cooler: Despite having a relatively large display and extremely powerful fans, you can find this cooler selling for $135 or less.

Let's take a look at the specifications and features of this eye-catching AIO, then we’ll go over thermal and noise benchmarks so you can decide if the Ocypus Sigma L36 Pro deserves to make our list of the best CPU coolers.

Cooler specifications

Features of Ocypus Sigma L36 Pro

▶️ Detachable 3.5-inch 640x480 resolution IPS display

It seems like the biggest trend in liquid cooling recently is AIOs with fancy displays on top of the CPU block, and Ocypus rides this trend, including a 3.5-inch IPS screen here that some users might find reminiscent of older PCs due to it’s VGA (640x480) resolution and 4:3 aspect ratio.

Many AIOs have the screen built into the CPU block, like Hyte’s THICC Q60. Other manufacturers offer the display and CPU block as separate components, and that’s how the Ocypus Sigma L36 Pro is designed.

When a display connects to the PC, but isn’t actually built into the CPU block, this opens up customization options that you might not think of normally. As you can see in the photograph above, I’ve got the display set up on a stool next to my computer desk, instead of inside my case. You’ll have to obtain a 9-pin header to USB-A (or C) adapter to use the device externally, but these can usually be found for less than $10.

To control and customize the display, you’ll need to download the simply named Ocypus Display software. It’s a surprisingly small download size of only 184 megabytes, and uses 493 MB when installed – and about the same amount of RAM when active.

Multiple preset themes are available, but only three are installed by default.

If you click the cloud icon shown in the picture above, a link to Ocypus' “Download Center” is opened in your default browser, which offers more options.

The software is extremely simple to use and easy to create your own customized theme with. In the example above, I uploaded an animated GIF file of a happy puppy and set the display to monitor CPU temperature, power consumption, and fan speeds metrics through text labels. I’ve also set up monitoring of CPU utilization, both with a text label showing the current status and a line graph showing the changes in CPU utilization over time.

▶️ RAM Clearance

As with most liquid coolers, the design of this AIO is such that the CPU block as such that it doesn’t overhang or interfere with the DIMM slots in any manner, ensuring that all sticks of compatible RAM, no matter how tall, will fit with this cooler.

▶️ Thick CPU cold plate

This AIO is designed for normal PC platforms like Intel’s Arrow Lake and LGA1851 socket or AMD’s Ryzen X3D CPUs and the AM5 socket, but you might wonder if it supports server products when you see the size of the coldplate – it has a larger surface area and greater thickness than most liquid coolers designed for consumer PCs.

▶️ 120mm fans

There’s more to a cooler than just the radiator and liquid pump. The included fans have a direct impact on aesthetics, noise levels, and overall thermal performance. Conveniently, the fans here arrive pre-installed, saving a few moments of time when you put things together. The fans included in this model are white, but this cooler is also available with black fans.

These fans seem to be overbuilt, more powerful than the rest of the AIO can properly take advantage of. They are rated for an unusually high 5.8 MMH20 of static pressure and 90 CFM at full speed.

▶️ Packaging

The outer packaging is a bit flashy, at least in comparison to your normal AIO box. It features a rendering of the cooler against a black background with streaks of purple hues – logos on all sides of the box for full marketing impact.

The inner packaging is just as fresh as the outside, with each component of the cooling system well protected from the chaos that shipping can bring by using a combination of soft covers and individual cardboard walls for each component.

Included with the package are:

• Mounting hardware for AMD and Intel platforms
• Tubing clips
• A small tube of thermal paste
• 360mm radiator and 120mm fans
• 3.5-inch LCD display

AM5 Installation

This section assumes you’ve already mounted the 360mm radiator. Installation of AIOs is typically much easier when you have already secured the radiator to your computer case. To begin putting things together, you’ll first need to remove the default AM4/5 retention hardware.

The next step is to screw in the mounting studs, as shown below.

Now you’ll want to apply the included thermal paste. If you’re not sure how to do that, we have a handy thermal paste application guide that covers the different methods you can use.

After thermal paste is applied, take the CPU block and press it against the studs, using the included screws and a screwdriver to secure it in place.

I chose to attach the included 3.5-inch screen externally, but if you want to place it in your case, this is the time to put it on top of your CPU block. The final step, of course, is to connect the cables and turn on your computer when finished.

Real-world testing configuration – AMD AM5 platform

We’ve tested coolers with both the Ryzen 9950X3D and its non-V-Cache sibling, the 9950X. There are some differences in how the 9950X and 9950X3D CPUs are impacted by thermal events. While the heat output of the CCDs of AMD’s 9950X3D is relatively balanced, the 9950X I used has one CCD that runs much hotter than the other, with a difference of over 10 degrees Celsius in some scenarios, shown below.

We’ve since returned to using a 9950X3D for cooler testing, as it has a more balanced heat profile, and is almost certainly a more widely adopted CPU. The benchmark results shared in these reviews may differ from others because I emphasize results that are comparable to real-world use. This means I generally test CPU coolers inside of a closed desktop case, which increases cooling difficulty compared to other testing methods.

Many reviewers test coolers on open test benches, which have a combination of lesser airflow needs and lowered ambient temperatures. This results in making weak coolers appear stronger than they really are. Some publications have also used generic thermal plates to test cooling solutions. I reject both of these methods because they don’t accurately reflect real-world cooler conditions.

Our latest testing setup uses the FLOVA F50 computer case from Tryx.

This case features a unique “crossflow” fan that pulls air from the side, which the company claims is more effective than traditional intake fans. For air cooling tests, we’ve added a single Noctua NF-A12 G2 intake fan.

PBO Performance and maximum noise levels

We’re going to start this review’s benchmark section by focusing on a traditional maximum performance test, with the CPU cooler’s fans allowed to reach their fastest speeds, for the best cooling possible.

Turning on PBO allows AMD’s Ryzen 9 9950X3D to stretch its legs to an extent and consume over 260W. Enabling PBO enables high power consumption and heat output, when using MSI’s X870E Carbon Wifi motherboard, the CPU will reach its TJ Max (peak temperature) of 95 degrees C (203 F) and thermally throttle to some extent with most coolers. When this throttling occurs, I’ve measured the average power consumption to determine performance.

High-end AIO liquid coolers have higher expectations in this benchmark, and are expected to be able to keep AMD’s Ryzen 9 9950X3D under TJ Max during the duration of the benchmark – in these cases, we compare the CPU’s actual temperature.

Ocypus’ Sigma L36 Pro performs well and is capable of keeping the CPU cool in this test, with an average temperature of 85.7C/186.3F.

Some coolers perform well in maximum strength tests, but run loudly at full speeds. Noisy fans in this scenario aren’t necessarily a bad thing; some folks prefer to hear them as a way to be aware when the CPU is getting hot.

The fans included with Ocypus’ Sigma L36 Pro reach 49.8 dBA at 100% RPM, which is loud, but to be expected of fans with 5.8mm H20 of air pressure. Those who prefer to implement speed restrictions for silent operation need not worry; our noise-normalized benchmarks show good performance even when the fans are set to run quietly.

200W thermal benchmarks

For the next thermal test, I leave the motherboard settings at their defaults, which results in a power limit of 200W when running Cinebench R23.

When compared to the other seven AIOs we’ve tested Ocypus Sigma L36 Pro against, its performance is behind most of its peers. That said, the gap between Ocypus’ AIO and the top performer is rather small – the average temperature of 70.5C (48.5C above ambient) achieved by the Sigma L36 Pro is only 2.1C behind our best result.

150W + GPU thermal results, noise levels

Our next test runs Cinebench on the CPU with a 150W power limit, while also running Furmark on MSI’s RTX 4070 Ti Super Ventus 3x OC. This causes the GPU to consume ~295W of power. This test is designed to emulate the thermals of games, which primarily stress the CPU and GPU.

Ocypus’ position in this thermal test remains the same as in our previous chart. When tied to the default fan curve of MSI’s X870E Carbon motherboard, it reaches a mild volume level of 41.9 dBA.

Noise-normalized testing

Most testing is performed with the cooler tied to the default fan curve of our MSI X870E Carbon motherboard, but some of y’all prefer to see tests when the noise levels of coolers are equalized. This is especially important to those of you who prefer silent computers. This next test has the CPU cooler noise-normalized to 38.9 dBA, with PBO enabled for the Ryzen 9 9950X3D CPU.Most coolers will not be able to keep the CPU from reaching its peak temperature (TJ Max) in this stress test. So we’ll look at this in terms of average CPU power consumption, which averaged 255.4 watts.

This test is especially difficult because in addition to the reduced noise from the CPU cooler, our current test bench’s system fans are configured to run extremely silently, below the floor of the noise meter I use to measure dBA.

Conclusion

Ocypus’ Sigma L36 Pro features an attractive combination of features, including a fancy 3.5-inch LCD display. Those things alone make this AIO interesting and worth considering, but it’s also affordable, with a regular price of only $135, and often on sale for less. In fact, as this review was wrapping up, the black version of the Sigma L36 Pro was on sale at Amazon for just $105. At that price, it’s inarguably a CPU-cooling steal.

Unlike some of its cooler competitors, Chiba Japan-based Scythe is a fabless company that partners with factories in China and Taiwan for manufacturing of its air coolers, fans, and other PC hardware. The company has been delivering cooling products aimed largely at quiet performance for more than 20 years. We’ve enjoyed testing its previous products, like the fan-favorite FUMA 3 air cooler. Today we’re looking at Scythe’s latest offering, the Magoroku – a dual tower heatsink paired with two of Scythe’s Wonder Tornado 120 fans.

Let's take a look at the specifications and features of this CPU cooler. Then we’ll go over thermal and noise benchmarks to see if the Magoroku deserves to make our list of the best CPU coolers.

Cooler specifications

Features of the Scythe Magoroku air cooler

▶️ Dual tower heatsinks, six copper heatpipes

This air cooler features a dual-tower design, with six copper heatpipes to move heat from the CPU block into the metal fins above.

▶️ RAM Clearance

RAM compatibility with this cooler depends on how you look at it. Officially, Scythe mentions support for RAM up to 57mm tall. However, using the fan with tall RAM in this configuration does result in some performance loss.

We instead recommend moving the front fan to the back of the unit, above your motherboard’s VRM heatsinks, for best thermal performance. This configuration also has the side effect of complete RAM compatibility, as nothing interferes with or overhangs the DIMM slots.

▶️ 120mm Wonder Tornado fans

There's more to a cooler than just the heatsink. The included fans have a direct impact on aesthetics, noise levels, and overall thermal performance. Scythe includes two of its Wonder Tornado 120 fans with the Magoroku air cooler.

▶️ Packaging

The outer packaging highlights the design of the product in a flashy but subtle way, incorporating a black background with grey and white highlights.

The CPU cooler and fans are protected by molded foam and cardboard inserts.

Included with the package are:

● Mounting hardware for AMD and Intel platforms

● Three sets of fan clips

● A small tube of thermal paste

● Two 120mm Wonder Tornado fans

● Screwdriver

AM5 Installation

To begin putting things together, you’ll need to first remove the default AM4/5 retention mechanism. Next, place the studs over the exposed holes.

Afterwards, take the mounting bars and secure them with the included screws and screwdriver.

It’s time to apply the thermal compound. If you’re not sure how to do that, we have a handy thermal paste application guide that covers the best methods you can use.

After thermal paste is applied, take the CPU block and press it against the mounting bars, using the built-in screws and screwdriver to secure it in place.

Finally, you’ll want to attach both fans using the clips included with the cooler and connect them to the motherboard’s PWM header. If you have tall system RAM, I advise moving the front fan and placing it in the rear for best thermal performance.

Real-world testing configuration on AMD’s AM5 platform

We’ve tested coolers with both the Ryzen 9950X3D and its non-V-Cache sibling, the 9950X. There are some differences in how the 9950X and 9950X3D CPUs are impacted by thermal events. While the heat output of the CCDs of AMD’s 9950X3D is relatively balanced, the 9950X I used has one CCD that runs much hotter than the other, with a difference of over 10 degrees Celsius in some scenarios, shown below.

We’ve since returned to using a 9950X3D for cooler testing, as it has a more balanced heat profile, and is almost certainly a more widely adopted CPU. The benchmark results shared in these reviews may differ from others because I emphasize results that are comparable to real-world use. This means I generally test CPU coolers inside of a closed desktop case, which increases cooling difficulty compared to other testing methods.

Many reviewers test coolers on open test benches, which have a combination of lesser airflow needs and lowered ambient temperatures. This results in making weak coolers appear stronger than they really are. Some publications have also used generic thermal plates to test cooling solutions. I reject both of these methods because they don’t accurately reflect real-world cooler conditions.

Our latest testing setup uses the FLOVA F50 computer case from Tryx.

This case features a unique “crossflow” fan that pulls air from the side, which the company claims is more effective than traditional intake fans. For air cooling tests, we’ve added a single Noctua NF-A12 G2 intake fan.

We’re going to start this review’s benchmark section by focusing on a traditional maximum performance test, with the CPU cooler’s fans allowed to reach their fastest speeds, for the best cooling possible.

Turning on PBO allows AMD’s Ryzen 9 9950X3D to stretch its legs to an extent and consume over 260W. Enabling PBO enables high power consumption and heat output, when using MSI’s X870E Carbon Wifi motherboard the CPU will reach its TJ Max (peak temperature) of 95 degrees C (203 F) and thermally throttle to some extent with most coolers. When this throttling occurs, I’ve measured the average power consumption to determine performance.

You’ll notice there are two results for Scythe’s Magoroku here. The first result is with an intake fan above our test rig’s TeamGroup DDR5 (as Scythe suggests); the second result is with that fan placed on the back above the motherboard’s VRM modules. As you can see, it’s better to move the front fan to the back if your system incorporates tall RAM modules. That said, neither result is particularly impressive. These are the worst results we’ve seen on our latest test bench.

Some coolers perform well in maximum strength tests, but run loudly at full speeds. Noisy fans in this scenario aren’t necessarily a bad thing; some prefer to hear them as a way to be aware when the CPU is getting hot. Scythe’s Magoroku has a maximum volume level of 43.4 dBA, which is on the quieter end of the fan noise spectrum.

200W thermal benchmarks

For the next thermal test, I leave the motherboard settings at their defaults, which results in a power limit of 200W when running Cinebench R23. The results here are slightly better than the last test, but not by much. The Scythe was the second-warmest cooler we’ve seen on this test bench.

150W + GPU thermal results

Our next test runs Cinebench on the CPU with a 150W power limit, while also running Furmark on MSI’s RTX 4070 Ti Super Ventus 3x OC. This causes the GPU to consume ~295W of power. This test is designed to emulate the thermals of games, which primarily stress the CPU and GPU.

We’ve got another fairly disappointing result here, with a CPU temperature of 69.9C (47.9C over ambient) – the thermal performance is again in last place. Noise levels in our 150W CPU thermal test were acceptable, though, reaching 39.6 dBA.

It’s worth pointing out that some games are more intensive than this test above. While playing Assassin’s Creed: Odyssey, I regularly noticed temperatures reaching near TJ Max. This is a bit concerning.

Noise-normalized testing

Most testing is performed with the cooler tied to the default fan curve of our MSI X870E Carbon motherboard, but some of y’all prefer to see tests when the noise levels of coolers are equalized. This is especially important to those of you who prefer silent computers. This next test has the CPU cooler noise-normalized to 38.9 dBA, with PBO enabled for the Ryzen 9 9950X3D CPU.

This test is especially difficult because, in addition to the reduced noise from the CPU cooler, our current test bench’s system fans are configured to run extremely silently, below the floor of the noise meter I use to measure dBA.

Most coolers, particularly air coolers, can’t keep the CPU from reaching its peak temperature (TJ Max) in this stress test. We’ll look at this in terms of power consumption, which averaged 228.7 watts. I wish I could say more positive things about this cooler’s thermal performance, but it just doesn’t seem to perform very well with an AMD Ryzen 9950X3D CPU.

Karhu DDR5 RAM thermals testing

Your CPU cooler does not operate in isolation. It has an impact on not just your CPU’s temperatures, but also the other components in your build, like your RAM and GPU. To that end, I’ve run the Karhu RAM stress test. This places a load of ~153W on the CPU and ensures system RAM (DDR5 in my case) is fully stable. In this type of scenario, most AIOs tend to produce worse results than air coolers.

While the rest of our test results weren’t very impressive, Scythe’s Magoroku performed well when it came to keeping system DDR5 temperatures under control, measuring at an average of 43C (21C over ambient), tied for our second-place result in this benchmark if you don’t count Silverstone’s AIO with extra VRM fans.

Conclusion

Scythe’s Magoroku is a nice-looking cooler with moderately low noise levels. But most of our thermal results were underwhelming with our AMD Ryzen 9 9950X3D test bench. The exception to this was DDR5 RAM temperatures, which were impressive. If you’re looking for a low-noise air cooler that effectively cools your system memory, you might be happy with this product.

Perhaps this cooler performs better on Intel systems, but for AMD users, I’d instead recommend Thermalright’s Royal Pretor 130 at this price point.

Modern smartphones pack enough computing power to rival budget PCs. However, one of the biggest limitations preventing mobile chips from sustaining peak performance is thermal throttling. To tackle the problem, a hardware enthusiast on Reddit carried out an experiment in the most absurd way possible, sandwiching a smartphone between two desktop CPU air coolers. The result is a miniature desktop PC built around a phone's motherboard that actually works and performs well.

The smartphone chosen for this project is the ZTE Nubia Z70 Ultra, which is powered by Qualcomm's Snapdragon 8 Elite SoC paired with 24GB of LPDDR5X RAM and 1TB of UFS 4.0 storage. It is worth noting that this particular chipset made its debut in 2024, with its prime CPU cores rated to reach up to 4.32 GHz. The latest Snapdragon 8 Elite Gen 5 is a more powerful chip and can go as high as 4.6 GHz. Rather than using a newer, higher-clocked chip, the project is essentially testing how much sustained performance can be extracted from an older Snapdragon flagship.

“It actually started from a pretty simple idea," the creator told Tom's Hardware. "I wanted to see how far I could push the concept of using a single smartphone as my main machine, instead of having a phone, a gaming console and a separate PC.”

To carry out the project, the smartphone was completely stripped down to its core by removing the camera hardware, mobile network hardware, as well as the display, which is cleverly mounted within the custom acrylic enclosure for the system. The creator then mounted two full-size desktop CPU heatsinks on each side of the phone hardware. The contact plates on the heatsinks, being large enough, could fully cover the main components, thus allowing improved heat dissipation compared to the original phone chassis.

The results are particularly impressive when it comes to sustained workloads. In the 3DMark Wild Life Extreme stress test, the setup achieved a 99% stability score over 20 loops. Its best loop produced a score of 6,980, while the lowest-scoring loop came in at 6,910, which is a mere 70-point difference. A screenshot also shows a 3DMark score of 10,533 in the ranking, putting the modified Z70 Ultra slightly ahead of the Samsung Galaxy S25+ powered by the same Snapdragon 8 Elite chipset.

The sustained performance is arguably more interesting compared to the peak benchmark numbers. Smartphones are designed around a difficult compromise where their processors can briefly operate at high performance levels. But due to the limited physical space for heat dissipation means sustained workloads eventually force the system to reduce clocks and power consumption.

“The long-term goal is basically one device that can cover Android, desktop Linux, Windows applications and PC gaming,” added the creator. Essentially, they wanted to keep Android at the core while having a desktop environment when connecting the setup to an external monitor, keyboard, and mouse. To achieve that, a custom Linux XFCE4 desktop environment was created using Termux, running directly on top of Android. The setup also supports hardware-accelerated Vulkan via Turnip on the Adreno GPU. Since the creator wanted to run Windows games locally on the Snapdragon hardware, they tinkered with Wine, Box64, and Hangover builds adapted and recompiled for the Linux environment, alongside GameNative.

The creator claims to have successfully run Windows applications and games, including The Witcher 3. The system was able to run the game at 1080p resolution with the Ultra graphics preset, delivering around 20–30 FPS. Notably, the GPU was sitting at approximately 99% utilization during gameplay, while certain scenes managed to exceed 30 FPS. That obviously isn't enough performance to turn the smartphone into a replacement for a modern gaming PC. However, it is impressive that a smartphone SoC can render a demanding PC game at 1080p using a compatibility stack designed to translate software between different CPU architectures and operating environments.

The project is anything but practical, as the two desktop CPU coolers make the original smartphone form factor essentially irrelevant. However, by giving the Snapdragon 8 Elite substantially more thermal headroom, the creator has turned a flagship smartphone into something that sits somewhere between a phone and a desktop PC. More importantly, it raises an interesting question about how much performance modern mobile chips are leaving on the table simply because they have to fit inside our pockets.

DeepCool has been delivering innovative, interesting, and often budget-conscious PC cases and cooling products for more than a decade. Its current lineup includes air and AIO coolers, computer cases, keyboards, power supplies, and other accessories.

We were impressed by the company’s AK620 and Assassin VC Elite air coolers in the past. In 2024, the Beijing-based company was banned from selling products in the U.S., but has continued to produce and improve its cooling products for markets elsewhere. US consumers also have the option of importing the cooler, if you don’t mind paying for extra shipping costs.

Here, we’re looking at DeepCool’s second-generation AK series coolers, the AK400 G2 and AK620 G2. These are available in two styles: one with woodgrain top covers, the other featuring a digital display.

Let's take a look at the specifications and features of the coolers, then we’ll go over thermal and noise benchmarks and decide if DeepCool’s AK G2 series coolers deserve to make our list of the best CPU coolers.

DeepCool AK620 G2/AK400 G2 specifications

Features of DeepCool’s AK G2 Air coolers

▶️ Heatpipes and heatsink

With the single-tower AK400 G2, four slightly staggered direct-touch copper heatpipes are embedded in the base to transfer heat from the CPU into the heatsink and its fins.

The larger, dual-tower AK620 G2 features six evenly spaced copper heatpipes.

The heatsink fin designs are similar in both models. The front ends feature a jigsaw-type design, shown below.

The exhaust side features the checkerboard matrix style DeepCool’s air coolers are known for, a design choice which the company says improves static pressure.

▶️ High-performance 120 mm fans

There’s more to a cooler than just the heatsink. The included fans directly impact noise levels and cooling performance. The fans included on both AK400 and AK620 G2 models are essentially the same – but the AK400’s single fan runs up to 10% faster than the two fans included with the AK620 G2.

▶️ Woodgrain and digital display styles available

Both the AK400 and AK620 are available in black or white, but there are two sub-choices for the aesthetic. The versions we’ve tested for this review feature woodgrain, a motif that’s been increasing in popularity in DIY PCs since the release of Fractal’s North computer case.

If you don’t like woodgrain, DeepCool also includes a checkerboard black cover that you can use in place of the woodgrain covers.

There’s also the Nyx version of the AK620 G2 available, which features a digital display showing CPU performance metrics – temperature, frequency, power consumption, and overall CPU usage.

▶️ RAM Clearance

The AK400 G2's design is such that it doesn’t overhang or interfere with the DIMM slots, ensuring that all sizes of RAM, no matter how tall, are compatible.

Standard-height DDR5 sticks 40mm tall fit well under the larger AK620 G2, but taller sticks won’t fit perfectly underneath. Our current CPU cooler test bench incorporates TeamGroup’s Sakura Rose T-Force Xtreem DDR5-7200 sticks, which are 48.8mm (1.92 inches) tall.

If you also use taller RAM DIMMs, you’ll have to raise the intake fan’s placement by a few millimeters for things to fit properly, as we did (see image, above). This might result in slightly lower cooling performance in certain scenarios. But even so, the AK620 G2 performed excellently, as you’ll see in the benchmarks section.

▶️ Packaging

The outer packaging is typical of DeepCool products: a basic brown box with a blue line and DeepCool’s logo, covered by a wraparound showing a picture of the cooler.

The heatsink and fans are protected by molded foam, and the accessories are contained in a small cardboard box. Included with the package are:

• Mounting hardware for AMD and Intel platforms
• Alternative top covers
• Screwdriver (AK620 G2 only)
• The AK620 G2 includes a tube of thermal paste; the AK400 G2 includes pre-installed thermal paste
• Single-tower (AK400 G2) or dual-tower (AK620 G2) heatsink
• 120 mm fans and fan clips
• Installation manual

▶️ AK620 G2 AM5 Installation

You’ll need to first remove the default AM4/5 retention mechanism and then place the mounting studs around the exposed screw holes.

The next step is to place the mounting bars on top of the studs, securing them with the included screws, and then apply the included thermal paste. If you’re not sure how to do that, we have a handy thermal paste application guide that covers the different methods you can use. Afterwards, place the heatsink tower against the CPU and mounting bars, and use a screwdriver to secure it.

Once the heatsink is secured, attach the 120 mm fans to the heatsinks. Lastly, connect the PWM cables of the fans to the corresponding headers of your motherboard.

Real-world testing configuration – AMD AM5 platform

We’ve tested coolers with both the Ryzen 9950X3D and its non-V-Cache sibling, the 9950X. There are some differences in how the 9950X and 9950X3D CPUs are impacted by thermal events. While the heat output of the CCDs of AMD’s 9950X3D is relatively balanced, the 9950X has one CCD that runs much hotter than the other, with a difference of over 10 degrees Celsius in some scenarios, shown below.

The benchmark results shared in these reviews may differ from others because I emphasize results that are comparable to real-world use. This means I generally test CPU coolers inside of a closed desktop case, which increases cooling difficulty compared to other testing methods.

Many reviewers test coolers on an open test bench, which has lesser airflow needs and lowered ambient temperatures. This results in weak coolers appearing stronger than they really are. Some have also used generic thermal plates to test cooling solutions. I feel that these methods don’t accurately reflect real-world cooler conditions.

Our latest testing setup uses the Flova F50 computer case from Tryx.

This case features a unique “crossflow” fan that pulls air from the side, which the company claims is more effective than traditional intake fans. For air cooling tests, we’ve added a single Noctua NF-A12 G2 intake fan.

PBO Performance and maximum noise levels

We’re going to start by focusing on a traditional maximum performance test, with the CPU cooler’s fans allowed to reach their fastest speeds, for the best cooling possible.

Turning on PBO allows AMD’s Ryzen 9 9950X3D to stretch its legs to an extent, and all air coolers I have tested with PBO enabled using MSI’s X870E Carbon Wifi motherboard reach the maximum CPU temperature of 95 degrees Celsius (203 degrees Fahrenheit) and thermally throttle to some extent.

Results from the liquid coolers we’ve recently tested aren’t shown above because they are able to keep AMD’s Ryzen 9 9950X3D under TJ Max, and as such, power consumption figures aren’t quite comparable.

The performance of DeepCool’s AK620 G2 is simply excellent, outperforming every air cooler we’ve tested on our current test bench. Its little sibling, the AK400 G2, also does fairly well for a single-tower air cooler, slightly outperforming Sudokoo’s SK620V and only trailing ID-Cooling’s AK620 SLK by 2.4W!

To give a wider variety of comparison examples, I’ve included a chart of the same tests from our last AMD Ryzen 9 9950X3D cooling test bench. But keep in mind these results aren’t 100% comparable, due to a different case and fans being used; the ambient temperature is also slightly higher with the results below.

Our newest test bench used for this and other recent reviews incorporates a Tryx crossblade intake fan as well as a single Noctua NF-A12 G2 intake fan, which results in better air cooling performance.

Some coolers perform well in maximum strength tests, but require running loudly to maintain said performance, but that’s not the case with DeepCool’s AK G2 air coolers. With measurements of 42.4 and 41.9 dBA respectively, their maximum noise levels put them among the quietest coolers featured in our charts.

200W thermal benchmarks

For the next thermal test, I leave the motherboard settings at their defaults, which results in a power limit of 200W when running Cinebench R23.

With this thermal test, DeepCool’s AK620 G2 slips to the second best result we got from any air cooler. The single tower version, the AK400 G2, still performs well in comparison to dual-tower products, besting Sudokoo’s SK620V and just a bit behind Montech’s NX600 with its powerful E28 fans.

150W + GPU thermal results, noise levels

Our next test runs Cinebench on the CPU with a 150W power limit, while also running Furmark on MSI’s RTX 4070 Ti Super Ventus 3x OC. This causes the GPU to consume ~295W of power. This test is designed to emulate the thermals of games, which primarily stress the CPU and GPU.

At first glance, you might think the results above – when tied to the default fan curve of MSI’s X870E Carbon motherboard – are a little underwhelming compared to the competing coolers shown in the chart.

But thermals are only part of the story. Noise levels, especially when you’re gaming, are far more important here. With a noise level of only 38.9 dBA measured, the loudness of these coolers won’t be an issue while you’re gaming. Your GPU fans and / or your case will likely be making more noise in most setups.

Noise-normalized testing

Most testing is performed with the cooler tied to the default fan curve of our MSI X870E Carbon motherboard, but many prefer tests with the noise levels of coolers equalized. This is especially important to those of you who prefer silent computers. This next benchmark has the CPU cooler noise-normalized to 38.9 dBA, with PBO enabled for the Ryzen 9 9950X3D CPU.

The results here are pretty good. With an average of 242.5W cooled during the course of testing, DeepCool’s AK620 G2 shows the second-best performance of the air coolers in this chart. The single-tower AK400 G2 is our bottom result, but even so, its performance is basically on par with Montech’s NX600. That’s fairly impressive for a single-tower air cooler.

Karhu DDR5 RAM thermals testing!

Your CPU cooler does not operate in isolation. It has an impact on not just your CPU’s temperatures, but also the other components in your build, like your RAM and GPU. To that end, I’ve run the Karhu RAM stress test. This places a load of ~153W on the CPU and ensures system RAM (DDR5 in my case) is fully stable. In this type of scenario, most AIOs tend to produce worse results than air coolers.

The DDR5 temperature recordings from this test seem to be within expectations compared to other dual-tower air coolers. Temperatures with DeepCool’s AK620 G2 were an average of 21.9C above ambient. Curiously, DeepCool’s single tower AK400 G2 showed the best RAM temperatures in this scenario of any air cooler.

The thermals of the CPU in this test were about as expected, with the AK620 G2 showing some of the best temperatures and the AK400 G2 running warmer than most of the dual-tower coolers here, but notably still outperforming Sudokoo’s SK700V.

Conclusion

DeepCool continues to impress with its second-generation AK air coolers, the AK620 G2 and AK400 G2, delivering strong thermal performance and low noise levels. Our only major complaint is that these coolers aren’t easily available for purchase in the USA. If you’d rather not go through the hassle of importing, our recommendation would be Thermalright’s Royal Pretor 130, which offers similarly strong thermal performance and low noise levels, at a more affordable price of $50 USD.

The fearless TrashBench has been testing direct die water cooling of graphics cards. The inevitable twist here is that they removed the metal waterblock from the equation. Despite initial leaky results and much concern of water damage to the expensive parts thrown into the mix, some of the end results are eyebrow-raising in a good way.

“In my pursuit of the perfect water block, I realized, why do we need metal at all?” queried the antipodean host of the punk-rock GPU death lab. “Why can't we just pump water directly over the bare silicon? Makes sense to me.”

TrashBench began this project well aware that leaks might be a problem. Thus, a non-working GeForce RTX 3060 was chosen for the initial feasibility tests. It was measured up for a 3D printed water block which would direct the coolant directly over the GPU die. Our hardware adventurer covered any surface-mount components beside the GPU with nail polish to prevent water damage/shorting.

Some tried and trusted plumbing measures were then applied, with the design incorporating washers, gaskets, and hose clamps (worm-screw equipped jubilee clips). Water pipe fittings were melted into the block, which was fastened using the retaining clamp mechanism that the air cooler had previously used.

This initial test sprang a leak, or two, so TrashBench decided to add epoxy adhesive to secure and seal the 3D printed block to the GPU. This worked, but then some water was spotted oozing from the tube fittings, so they got a dose of epoxy too. At last, we had the first non-leaky prototype…

After some live runs using a powered-up GTX 980 were successful, it was time for the main event with fitting, testing, and benchmarking using an RTX 2060 Super. On the way, it was noticed that the choice of 3D print material used on TrashBench’s Bambu Lab 3D printer wasn’t trivial. Some materials leaked from the edges, and others were actually slightly porous. During live power tests, the TechTuber wisely used a PCIe riser cable so any leaks wouldn’t immediately drip onto the motherboard.

Was it worth it?

If you like to live dangerously, it could be argued that the TrashBench results show some value in this cooling methodology. The headlining technique was compared against the stock cooler and a clamped-on AiO cooling solution.

Going by the numbers above, you can see that direct water cooling could be interesting, as long as you can ensure long-term confidence about leakage. In the video, you can also see some interesting extras, like running this system using -28°C coolant. The same trick is also tested using an Intel i5-7600K CPU. That was chosen as “it’s not a particularly hot CPU, but if it dies, I don’t care.”

The eventual conclusion was that chamber size matters (most clearly illustrated by the CPU cooling test), but pumping water directly over silicon can work.

It is not a secret that proper cooling ensures longevity and enables hardware to demonstrate its full potential. But when it comes to data center AI hardware, proper cooling also means higher sustained performance, which directly translates into money earned by the owner. Frore Systems, a maker of cooling solutions that are made using semiconductor-grade tools, seems to have a perfect idea of how to reduce the temperature of next-generation AI accelerators and increase their performance by 15%.

Frore Systems last week published a white paper which suggests that improvements to the entire cooling stack — from the GPU packaging and thermal interface materials (TIMs) to coldplates and coolant temperatures — can increase token generation per watt by more than 30%. Meanwhile, one of the company's boldest projections based on an analytical thermal model* is that its LiquidJet coldplate technology alone can lower Nvidia Rubin GPU junction temperatures by up to 12°C, which translates into a 10% to 25% improvement in tokens/Watt, while a 10°C reduction could increase token generation by around 15%.

Indeed, modern AI accelerators, such as the upcoming Nvidia Rubin, can dissipate up to 2,400 W, and their die temperatures can easily hit 95°C or more. But while 95°C is not necessarily a problem for silicon longevity, leakage current certainly is. Leakage current rises exponentially with temperature, approximately doubling for every 10°C increase in maximum junction temperature, which is when transistor switching itself also becomes less efficient. As a consequence, hotter GPUs require higher voltages to sustain clocks, which eventually forces Dynamic Voltage and Frequency Scaling (DVFS) to reduce clocks to remain within thermal limits, which in turn will reduce performance and token generation.

This all leads to a simple conclusion: the better the cooling, the higher the performance and token output. Which is generally right. However, cooling is not as simple, as it depends on multiple factors that can be optimized. Furthermore, for AI data centers, cooling itself is no longer a way to preserve CPUs and accelerators from overheating, but really is a way to maximize their performance and token money generation.

Nvidia designs its platforms around Tj(max) temperature; it is one of the fundamental design constraints for the GPU, package, and cooling solution. This works like this:

• Nvidia specifies a maximum allowable junction temperature (Tj,max limit). This is the temperature the silicon must not exceed during normal operation. The exact value is not always public, but Frore uses 95°C for Rubin in its analysis.
• The GPU continuously monitors its junction temperature using tens or hundreds of on-die thermal sensors, yet power management monitors the hottest region.
• DVFS attempts to maximize performance while staying below the thermal and power limits, so if the GPU has thermal headroom, it can sustain higher clocks or lower voltage. If the junction temperature rises, the firmware gradually adjusts voltage and frequency. If necessary, it throttles to prevent exceeding Tj(max).

The problem is that GPUs operate under several simultaneous limits, such as thermal limit (Tj,max), package power limit, current limit, and voltage limit. Usually, power is reached before thermal. Meanwhile, modern cooling systems are designed to prevent silicon from reaching Tj(max). So, even if Nvidia's GPU never reaches Tj(max), lowering the operating junction temperature still improves efficiency because transistor leakage decreases as temperature falls. This is where Frore and its cooling systems come into play.

According to Frore, leakage power approximately doubles for every 10°C increase in junction temperature, while transistor switching power rises by about 2% over the same temperature range, so lowering operating temperatures is beneficial even when the processor is not thermally throttling.

Thermal resistance

According to Frore, the maximum GPU junction temperature used by hardware makers is directed by a deceptively simple equation:

Tj(max) = Tinlet + Q × Rtotal

where coolant inlet temperature, GPU power, and total thermal resistance determine how hot the silicon can be. Meanwhile, total thermal resistance depends on three major elements: the GPU package itself, the thermal interface material between the package, and the coldplate design. As each layer adds thermal resistance, it increases die temperature and reduces overall token money generation. That said, thermal resistance is becoming a major problem, according to the paper.

Frore claims that delidding the Rubin package dramatically lowers thermal resistance (while this is obvious, I must add again that the paper is based on an analytical thermal model*). According to the paper, an unlidded Rubin package can reduce junction temperature by as much as 20°C compared to one with an integrated heatspreader (IHS), which potentially improves tokens/Watt by up to 35%. Of course, there are disadvantages, as delidded GPUs have lower mechanical reliability. We will talk about it later on. In any case, there are cloud system providers that explore the use of delidded Rubin GPUs to boost their token money generation despite all the risks, according to Frore.

Frore's own contribution is, of course, its coldplate. Conventional coldplates are typically manufactured using skiving, a machining process that creates long, straight microchannels inside a copper block. Frore instead borrows manufacturing techniques from semiconductor fabrication — etching and bonding — to build intricate three-dimensional copper microstructures that address hotspots on the accelerator's silicon. These unique microstructures cannot be produced using traditional machining, at least not cost-efficiently, according to Frore.

Improving efficiency

The LiquidJet design features short microchannels that are etched around hot spots, multiple cooling stages, and flow routing optimized for the GPU's power-density map. According to the company's analysis, this enables a 6°C to 12°C reduction in junction temperature and improves tokens/Watt by 10% to 25% in the case of the Nvidia Rubin GPU*. A roughly 10°C temperature reduction would therefore correspond to about a 15% increase in token generation efficiency, the paper claims.

Frore argues that improved coldplate efficiency changes the economics of facility cooling, which is obviously the most important part of the hyperscalers' consideration. Nvidia designed Rubin to operate with coolant entering at up to 45°C, which enables many AI data centers to rely entirely on 'free' cooling without mechanical chillers. While lowering the inlet temperature can further improve GPU efficiency, doing so only makes economic sense if the energy consumed by the chillers is offset by the resulting increase in money token generation. Meanwhile, because LiquidJet requires a lower coolant flow rate to maintain the same junction temperature, it also reduces the chiller coefficient of performance (COP) required for additional cooling to become worthwhile.

In Frore's example, a Rubin GPU equipped with a conventional skived coldplate requires a chiller COP of approximately 6.7 before colder coolant delivers a net efficiency benefit, whereas LiquidJet lowers the break-even COP to around 4.1, which makes mechanical chilling economically attractive across various deployments.

One interesting thing about Frore's analysis is that its LiquidJet is more efficient on Rubin data center GPUs compared to Blackwell data center GPUs* due to the higher transistor density of the former.

Frore's analysis does not stop at exploring the advantages of its own cooling systems, so the company's analytical thermal model extends to other means by which improved cooling and/or lowered thermal resistance can affect temperatures and therefore money token generation.

One of the most striking claims by Frore concerns Nvidia's upcoming Rubin is that Frore claims that delidding the GPU package — removing the IHS and the graphene TIM placed between the die and the lid — dramatically lowers thermal resistance, which therefore reduces junction temperature by as much as 20°C compared to regular GPUs with IHS, which therefore improves tokens per Watt by up to 35%, according to the model used by Frore.

Meanwhile, mechanical reliability becomes a major concern for delidded GPUs. Without the IHS, the bare Rubin GPU packaged using TSMC's CoWoS-L technology becomes considerably more vulnerable to cracking of bridges that connect the two Rubin dies. In fact, even in the Hopper era, some GPUs literally cracked with certain liquid coolers. Furthermore, maintaining uniform contact pressure across multiple exposed dies is substantially more difficult than in the case of monolithic processors. Nonetheless, there are hyperscalers that are exploring the use of delidded Rubin GPUs to increase their token generation and money output.

Thermal interface materials play an equally important role. By default, Nvidia's Rubin reportedly addresses the thermal penalty of a lidded package by using liquid indium metal TIM with gold-plated contact surfaces. Frore argues that an unlidded package paired with a high-performance phase-change material such as PTM7950 still exhibits lower overall thermal resistance than a lidded package using liquid metal, which turns into as much as a 14°C junction-temperature advantage and up to a 28% increase in money tokens/Watt, according to Frore's model.

Summary

The key point of Frore's white paper is that cooling has become a key determinant of AI data center profitability, as lower GPU junction temperatures improve token generation efficiency rather than 'just' preventing overheating.

In a white paper based on an analytical thermal model, the company claims that its LiquidJet coldplate can lower Nvidia Rubin junction temperatures by 6°C to 12°C and increase tokens/Watt by 10% to 25%, while a 10°C reduction could boost token generation by about 15%.

In addition, the company argues that more efficient coldplates make mechanical chilling economically viable across a wider range of AI data centers as it lowers the break-even chiller efficiency required to offset cooling power consumption.

Finally, Frore claims that delidding Rubin and optimizing thermal interface materials can reduce thermal resistance further and improve tokens/Watt by up to 35%, albeit at the cost of greater mechanical risk for these accelerators.

*It should be noted that Frore's analysis is based on an analytical thermal model rather than experimental results. The paper builds on the thermal resistance equation (Tj = Tinlet + Q × Rtotal), published or assumed operating parameters for Nvidia's Rubin GPU, and the company's own estimates of how different coldplate designs affect thermal resistance.

Following a tariff refund from the United States government, popular PC cooling hardware manufacturer Arctic has announced a price rollback for its products sold in the U.S. The refund was made possible after a February 2026 Supreme Court ruling found that the 1977 International Emergency Economic Powers Act (IEEPA) does not grant the President unilateral authority to impose import duties without prior approval from Congress.

• New low prices on Arctic cooling at Amazon

The reduced price will be applicable across Arctic’s direct-to-consumer sales channels in the U.S. and is claimed to be already in effect on Amazon and eBay. In its latest blog post, Arctic said, “When U.S. trade tariffs significantly increased, Arctic proactively absorbed as much of the tariffs as possible to protect our customers. While most of the product lineup remained unaffected, price adjustments became necessary for a limited number of products in the U.S. market. At the time, Arctic committed to reversing those increases if circumstances allowed. “

Notably, the company isn't limiting price reductions only to the products that were affected by tariffs. Instead, it's using the refunded tariff money to lower prices across its entire U.S. product lineup. We did a quick price check on Amazon and found that a range of Arctic PC cooling products have indeed dropped in price. For example, the Arctic Liquid Freezer III Pro 360mm AIO liquid cooler has fallen to an all-time low of $69.89, its lowest price ever since it launched in the first half of 2025. In our testing, we were impressed by its chart-topping performance even when it retailed for $125.

In addition to the price rollback, the company says that it is investing in community initiatives that support technology education and grassroots PC communities in the United States through hardware donations and technical support.

With this announcement, Arctic has become one of the first PC hardware manufacturers to publicly reverse tariff-related price increases following the landmark Supreme Court judgement. While it remains to be seen whether other component and peripheral makers will follow suit, the move will definitely put pressure on brands that previously cited tariffs as a reason for raising prices in the U.S.

Mechanical pressure serves as a better system to design computers around than natural buoyancy, but a new experiment from der8bauer is attempting to challenge that notion. The legendary modder recently built a chimney to exploit the "stack effect," which uses temperature differences to catalyze natural convection to the point where it becomes effective again. As a result, the CPU in his test bench saw temperatures drop by 19 degrees Celsius without any fans.

The video above explains the concept of the stack effect pertaining to its foundation, natural convection, in great detail. Also known as the chimney effect, it relies on differences in indoor-to-outdoor air density, which are dictated by differences in temperature and humidity. The bottom of the chimney becomes a low-pressure zone, sucking in cold air that escapes through the low-pressure exit at the top.

In the experiment, der8auer uses a fog machine to show how a radiator can't "pull" air without fans attached to it; the hot air dissipating from the other side is forced to fall back on natural convection. The test bench was water-cooled and consisted of an AMD Ryzen 7 9800X3D, so he added a temperature probe to the fittings to monitor the water temp as well. The experiment then begins with the first 3D-printed chimney that's 10cm tall — it barely works, but temps already start to drop by 0.5 degrees.

At this point, the water was at 61°C and der8auer added another 20cm chimney atop the previous one, making the enclosure 30cm tall in total. This made the temps drop by another 5 degrees over a 30-minute stabilization period. The fog machine didn't really show any difference in the airflow, however. Now, it was time for the big boy: an 80cm tall chimney made up of 4x 20cm parts, bringing the total height to 110cm.

Right away, temperatures began dropping below 55°C before the modder could even set up his camera for the ultrawide framing this setup warranted. Just five minutes later, the water had hit 50°C, but the visual demonstration really sealed the deal. Turning on the fog machine underneath the radiator showed air being pulled through the chimney as if there were fans facilitating airflow on top.

The CPU temperatures had peaked at 90°C previously, but the "big tower" had now brought them down to just 71°C, as reported by HWiNFO. The experiment was a raging success. The video ends with der8auer actually tying the stack effect back to how we use fans in modern PCs to synthesize air pressure, since they achieve the same goal — a pressure differential — just more reasonably. So, unless you want to redefine what a tower PC means, sticking to regular, boring old fans is enough.

A PC gamer has DIYed a passive Nvidia GeForce RTX 4060 graphics card system. Perhaps unhappy with the Palit GeForce RTX 3050 KalmX 6GB still being the pinnacle of commercial passive graphics cards in 2026, Bilibili user NexFrame (h/t Fanless Tech) has bolted a hulking finned aluminum heatsink onto an RTX 4060.

NexFrame appears to be a small or up-and-coming ‘brand’ with a penchant for passive PC systems, from what we can understand from their Bilibili bio (machine translation). Unfortunately, we don’t have a lot of information about this passive 5.5-pound (2.5kg) aluminum heatsink-wearing RTX 4060, like whether it is tuned to run cooler than a standard model for fanless operation.

Squinting at the Bilibili video source, a system monitor window seen towards the end of the video appears to show that the GPU is running in a gaming scenario at 58C, with a 71C hotspot. Meanwhile, the graphics fan is running at 0 RPM, which seems accurate. However, the modder doesn’t seem to be taking it easy on the GPU. Further down the system info screen, we see the GPU reportedly pulling 198W. A standard actively cooled RTX 4060 would consume far less than that under load, more like 115W to 120W, so some data must be mangled here, or being misreported.

Elsewhere in the images shared by NexFrame, we can see that the CPU is also being cooled passively. It looks like a hexacore Intel CPU has been combined with a Noctua NH-P1 Passive CPU cooler. This commercial passive cooler was capable of keeping a CPU consuming up to 75W cool and stable enough over extended periods during our review testing. The system monitor tool overlaid on NexFrame’s game testing session shows the CPU sipping between 35 and 50W.

Passively cooled PCs are of interest to a significant number of enthusiasts for eliminating what is typically the noisiest component of a modern PC – fans. In a standard gaming PC, there will be fans built into the CPU cooler, on the GPU shroud, in the PSU, and also arranged at strategic places around the case. Even so-called liquid cooling systems usually rely on their CPU or GPU contact heatsinks being attached to an array of fans cooling a radiator in the case. Just think how blissfully peaceful your computing experience could be if all these moving parts were eliminated.

TrashBench recently decided to test whether adding more and more fans to what used to be one of the best graphics cards would improve its performance. The result wasn’t significantly faster performance, sadly, even when the thermal headroom was used for overclocking (vs. stock OC). Nevertheless, lessons were learned, and the self-described “punk-rock GPU death lab” was still proud of the temperature reductions, plus the GPU contraption's “awesome” looks and sounds.

The experiment began with an overview of the Asus ROG GeForce RTX 3080, a nice example of the breed. But it was a choice that would perhaps end up making the 11-fan wonder look like less of an accomplishment. TrashBench stated the goal was to add more and more fans, plus duct tape and cable ties, then see whether the reduced temperatures from the boosted airflow result in more frames.

After cleaning and repasting the guinea pig GPU, a baseline was set with the stock cooler. Running 100% fan speed on the Asus ROG resulted in a stable temperature of 63°C (down from 70°C) during stress testing with the Unigine Heaven benchmark.

Replacing the Asus ROG cooling shroud with a trio of Arctic case fans dropped the reported GPU temperatures to a stable 52 degrees Celsius. That’s a decent result. Next, the trio of case fans was swapped for thicker server fans, shaving another 2 degrees Celsius off the GPU temperature, bringing it to 50 degrees Celsius precisely. Duct tape was added to prevent air venting from the sides of the server fans. Oops, the GPU temperature actually stabilized at a warmer 54 degrees Celsius.

So, that was the end of fans-at-the-front modifications. TrashBench next looked at adding a quintet of tiny Arctic server fans that run at up to 15,000 RPM along the top of the card. This jet-engine-soundalike configuration didn’t shift the needle, though. The RTX 3080 still wouldn’t hold below 50 degrees Celsius when tested for any length of time.

Trying backplate fans was the next idea. After another ineffective endeavor, though, TrashBench decided to upgrade the backplate fan to an AiO 360mm cooler. Wow - a new best was recorded with this setup, with the GPU reporting a top stable temperature of just 41 degrees Celsius in Heaven.

Momentarily happy with this low-temperature achievement, the tech tinkerer decided to check whether benchmark runs in Shadow of the Tomb Raider showed any benefit. There were some performance uplifts charted, but only very modest, as you can see from our results table, which even includes cases where the newfound overclocking headroom was taken advantage of.

TrashBench concluded with some positives. “It nearly cut the temperatures in half. It looks awesome. It sounds awesome,” underlined our hardware hacking hero. However, the tech tinkerer kept it real by adding “And it got me 2 FPS. So, not worth it.” In some ways, then, the good quality of the stock triple-fan Asus ROG RTX 3080 graphics card detracted from the 11 extra-fan hijinks.