There’s a unique thrill that comes with building a Small Form Factor (SFF) PC. It’s a puzzle of engineering and patience, a quest to cram immense power into the smallest possible chassis. I’ve spent countless hours meticulously planning cable routes, measuring component clearances down to the last millimeter, and celebrating the tiny victory of a side panel closing without a bulge. But there is one component that consistently throws a wrench in the works: the CPU cooler. Standard tower coolers are out of the question. Even many so-called “low-profile” options are too bulky. The wrong choice means a build that won’t close, a CPU that thermal throttles into oblivion, or being forced to use an underpowered stock cooler that sounds like a jet engine. This isn’t just an inconvenience; it’s a fundamental barrier to achieving the dream of a compact, quiet, and powerful rig. The search for a cooler that is diminutive in size but mighty in performance is the holy grail for any serious SFF enthusiast, which is exactly what led us to get our hands on the Thermalright AXP90 X36 Low Profile CPU Cooler 36mm.
- Compact, premium-quality low-profile CPU cooler (36mm total height)
- Good adaptability, all metal platform, with back plate fastener, secondary reflow soldering process
- Support for Intel: 115X/1200; AMD: AM4
What to Consider Before Buying a Low-Profile CPU Cooler
A CPU cooler is more than just a fan on a block of metal; it’s the critical component that dictates your processor’s stability, performance, and longevity. In the world of SFF builds, its role is even more pronounced. It’s the key solution for dissipating heat in a cramped environment where airflow is inherently restricted. The main benefits are unlocking your CPU’s full potential by preventing thermal throttling, reducing system noise compared to inadequate stock coolers, and enabling the very possibility of building in ultra-compact cases that were previously untenable for high-performance components. It transforms a potential hotbox into a stable and reliable machine.
The ideal customer for this type of product is someone deeply invested in the SFF PC building scene, from console-sized gaming rigs to slim home theater PCs (HTPCs) or even custom projects in unconventional enclosures, like the user who fitted one into a vintage Mac G4 case. They are builders for whom every millimeter of clearance is precious. Conversely, this type of cooler might not be suitable for those with standard ATX or Micro-ATX cases. If you have ample space, a larger tower cooler or an AIO liquid cooler will almost always provide better thermal performance and quieter operation for high-TDP processors. For those users, the extreme compactness of a sub-40mm cooler is an unnecessary compromise.
Before investing, consider these crucial points in detail:
- Dimensions & Space: This is the number one priority. Measure your case’s maximum CPU cooler height clearance. For the Thermalright AXP90 X36, that magic number is 36mm. You must also consider clearance around the CPU socket for RAM modules with tall heat spreaders and motherboard VRM heatsinks. An ill-fitting cooler is a non-starter.
- Capacity/Performance: Look at the cooler’s Thermal Design Power (TDP) rating, if available, and compare it to your CPU’s TDP. While not a perfect metric, it gives a general idea of its cooling capacity. Key features to look for include the number and diameter of heatpipes (four 6mm pipes is excellent for this size), the fan’s maximum RPM, and its airflow capacity (CFM). Higher numbers generally mean better cooling potential.
- Materials & Durability: Premium coolers use copper for the base and heatpipes due to its superior thermal conductivity, with aluminum fins for heat dissipation. The Thermalright AXP90 X36 Low Profile CPU Cooler 36mm uses this exact combination, along with a full metal mounting platform, which inspires much more confidence than the plastic brackets found on cheaper models. Look for signs of quality construction, like soldered fins and a nickel-plated finish to prevent oxidation.
- Ease of Use & Maintenance: Installation can be a major pain point, especially in SFF builds. Check if the cooler requires a backplate (most secure ones do), which means you need access to the back of your motherboard. The clarity of instructions and the quality of mounting hardware are also vital. Long-term, dust buildup is the main enemy, so a fan that’s easy to remove for cleaning is a significant plus.
Considering these factors will ensure you select a cooler that not only fits your build physically but also meets your performance and acoustic expectations.
While the Thermalright AXP90 X36 Low Profile CPU Cooler 36mm is an excellent choice for its specific niche, it’s always wise to see how it stacks up against the competition. For a broader look at all the top models for various build types, we highly recommend checking out our complete, in-depth guide:
- [Brand Overview] Thermalright is a Taiwan brand with more than 20 years of development. It has a certain popularity in the domestic and foreign markets and has a pivotal influence in the player...
- Cool for R7 | i7: Four heat pipes and a copper base ensure optimal cooling performance for AMD R7 and *Intel i7.
- 【Ø6mm Copper Heat Pipes】For effective heat dissapation Six Copper Heat Pipes oriented in a U-Shape join up in an Aluminum Fin Stack, for a TDP of up to 500W.
First Impressions: Dense, Dark, and Deceptively Capable
Unboxing the Thermalright AXP90 X36 Low Profile CPU Cooler 36mm, the first thing that strikes you is its density. It feels surprisingly hefty for its minuscule size, a testament to its all-metal construction and tightly packed fin stack. There’s no flimsy plastic to be found here. The entire heatsink is coated in a sleek, matte black finish that looks premium and helps it disappear into the shadows of a dark-themed build. The four 6mm copper heatpipes are neatly integrated, and the contact plate is smooth, though not a mirror polish. Pre-installed is the 92mm, 15mm-thick TL-9015B PWM fan, which feels solid and is held on by simple wire clips.
Inside the box, Thermalright provides everything needed for installation across a wide range of modern sockets: a universal backplate, separate mounting brackets for Intel and AMD, screws, standoffs, and a small tube of their own thermal paste. The inclusion of hardware for the latest AM5 and LGA 1700 sockets is a huge plus, ensuring forward compatibility. Compared to stock coolers, the difference in build quality is night and day. Compared to other low-profile competitors, the build quality feels a step above many similarly priced options, offering a feature set that really sets it apart in the ultra-compact market.
Key Benefits
- Extraordinarily low 36mm height is compatible with the tightest SFF cases
- Excellent cooling performance for its size, taming mid-range CPUs with ease
- Premium all-metal build quality with four copper heatpipes
- Broad socket compatibility, including modern AM5 and LGA 1700
Potential Drawbacks
- Installation process can be frustrating due to unclear instructions and a back-mounted design
- Fan can become noticeably loud at higher RPMs under heavy load
Deep Dive: A Performance Analysis of the Thermalright AXP90 X36
A compact cooler can look great, but its true worth is measured in degrees Celsius and decibels. We put the Thermalright AXP90 X36 Low Profile CPU Cooler 36mm through its paces in a notoriously cramped ITX chassis to see if its performance lives up to its promising design. We focused on the three areas that matter most to SFF builders: installation difficulty, raw thermal performance, and the acoustic experience.
Installation and Mounting: A Double-Edged Sword
Let’s address the most contentious aspect of this cooler right away: the installation. User feedback is sharply divided, with some calling it straightforward and others describing it as an absolute nightmare. Our experience lands somewhere in the middle, and we can see why it causes frustration. Unlike stock coolers or some other designs that mount from the top, the AXP90 X36 utilizes a backplate and secures with four screws from the *rear* of the motherboard. This immediately means that in 99% of cases, you must remove the motherboard completely from the case to install or remove the cooler. For SFF builders who are constantly tinkering, this is a significant drawback.
The instructions are purely pictorial and can be confusing. We found ourselves, like some users, having to study them a couple of times to grasp the correct orientation of the brackets and backplate. The biggest issue we encountered, and one echoed by a frustrated user who bent their mounting arms, is the lack of guidance on screw tension. There are no torque specs or spring-loaded screws to provide feedback. You simply tighten until you feel it’s “enough.” It’s very possible to over-tighten, which can cause bowing and improper contact with the CPU’s integrated heat spreader (IHS), leading to poor thermal performance. We recommend tightening in a cross-pattern, a quarter-turn at a time, until the screws are snug but not cranked down with excessive force. While we didn’t experience the stripped screws another user reported, we can see how the combination of soft screw heads and an awkward angle could lead to it. Despite these hurdles, once mounted, the system is incredibly secure. The all-metal backplate provides excellent pressure and ensures the cooler isn’t going anywhere, which is a big plus for systems that might be transported.
Thermal Performance: Punching Far Above its Weight
Once the installation woes are behind you, the Thermalright AXP90 X36 Low Profile CPU Cooler 36mm begins to shine. We paired it with an AMD Ryzen 5 5600G, a 65W TDP processor that is a popular choice for compact gaming and media builds. In our testing, the results were genuinely impressive for a cooler of this stature. At idle, temperatures hovered just a few degrees above ambient. Under a sustained, multi-core synthetic load, the CPU temperature stabilized at a very respectable 73°C. This aligns perfectly with user reports, such as one owner keeping the same CPU “consistently under 75C under load.” Another user reported their 65-watt CPU never exceeded 60°C, which is a fantastic result likely achieved in a case with better-than-average airflow.
What’s truly remarkable is how it handles CPUs pushed beyond their stock limits. We were skeptical, but one user’s report of keeping an Intel Core i3-12100F overclocked to 5 GHz under 90°C is a testament to the cooler’s capability. This potent performance can be attributed to its excellent design: four 6mm heatpipes utilizing Thermalright’s AGHP (Anti-Gravity Heat Pipe) technology, which they claim ensures efficiency regardless of orientation, a dense fin stack, and the capable TL-9015B fan pushing up to 42.58 CFM of air. For its 36mm height, we believe it’s one of the most powerful cooling solutions available, allowing SFF builders to use CPUs they might have previously thought required a larger, bulkier cooler. You can see its full specifications and impressive technology on its product page.
Acoustic Profile and SFF Compatibility
No component in an SFF build exists in a vacuum. A cooler’s physical dimensions and noise output are just as important as its raw cooling power. On the noise front, the AXP90 X36 is a mixed bag. At idle and during light workloads like web browsing or video playback, the 92mm fan is very quiet, easily fading into the background hum of the system. However, physics is unavoidable. To move a significant amount of air through a dense heatsink, a small fan has to spin fast. As the CPU load increases and the fan ramps up towards its 2700 RPM maximum, it becomes clearly audible. It’s not a high-pitched whine, but rather a distinct “whoosh” of air movement. As one user aptly put it, it’s “a bit on the noisy side but this should be expected for something so compact.”
For most users, this is a perfectly acceptable trade-off for the thermal performance and size. We highly recommend setting a custom fan curve in your motherboard’s BIOS. By allowing the CPU to run a few degrees warmer before the fan spins up aggressively, you can create a much quieter day-to-day experience, reserving the higher fan speeds for intense gaming sessions or heavy workloads where noise is less of a concern. The most compelling feature, however, remains its compatibility. At just 36mm tall, it is, as multiple users noted, barely taller than standard-height RAM modules or the motherboard’s own I/O shield. This makes the Thermalright AXP90 X36 Low Profile CPU Cooler 36mm a true problem-solver, enabling builds in ultra-thin cases like the Fractal Design Node 202 or Louqe Ghost S1 where even 47mm coolers won’t fit.
What Other Users Are Saying
Synthesizing feedback from other builders confirms our own findings, painting a picture of a product with high highs and some notable lows. On the positive side, the sentiment is overwhelmingly strong regarding its performance-to-size ratio. One user stated, “For the price, nothing else beats this in this size/form factor,” a sentiment we wholeheartedly agree with. Another praised it for keeping their CPU cool while being “barely taller than the RAM,” highlighting its core value proposition for space-constrained builds. Its ability to solve clearance issues is a recurring theme, with one builder noting it was the perfect solution for a custom Mac G4 PC conversion where no other aftermarket cooler would fit.
However, the negative feedback is just as consistent and centers almost exclusively on the installation process. “I too couldn’t understand the terribly written instructions,” one builder lamented, after spending hours on what should have been a simple task. Another had a harrowing experience with “cross threaded and already stripped screws” when trying to swap the mounting bracket, vowing never to buy from the brand again. There are also isolated reports of compatibility issues, with one user claiming it could not be installed on their AM5 socket, which contradicts the product’s official specifications and our own understanding. This may point to a specific motherboard incompatibility or user error, but it’s a data point worth considering.
How Does the Thermalright AXP90 X36 Compare to the Alternatives?
The Thermalright AXP90 X36 Low Profile CPU Cooler 36mm operates in a very specific niche. Comparing it to larger tower coolers isn’t a matter of which is “better,” but which is right for the specific build. While it’s an exceptional choice for SFF systems, if you have a standard case with more room to spare, other options may serve you better. Before you make your final decision, it’s worth seeing what else is available when size isn’t your primary constraint. It’s important to check the latest price and availability of the AXP90 X36 before comparing.
1. be quiet! Dark Rock Pro 5 CPU Cooler
- Dark Rock Pro 5 features 7 high-performance copper heat pipes and a special black coating with ceramic particles. This high-end CPU cooler achieves low temperatures even during periods of peak CPU...
- The 2 Silent Wings PWM fans feature advanced fluid-dynamic bearings, smooth 6-pole motors and airflow-optimized fan blades. The front fan provides extremely high air pressure, thanks to a...
- A Speed Switch allows you to choose between Quiet and Performance Modes, which control the maximum fan speed. Quiet Mode provides a maximum fan speed of up to 1500r/min and is perfect for normal...
The be quiet! Dark Rock Pro 5 represents the opposite end of the air-cooling spectrum. This is a massive dual-tower behemoth designed for maximum thermal dissipation and near-silent operation. With seven high-performance copper heatpipes and two Silent Wings fans, it’s built to cool the most demanding, high-TDP CPUs on the market, even with significant overclocking. A user choosing this over the AXP90 X36 would have a large ATX case and prioritize absolute peak performance and acoustics above all else. It is fundamentally incompatible with any SFF case that the AXP90 X36 is designed for.
2. be quiet! Dark Rock 5 CPU Air Cooler
- With 6 high-performance copper heat pipes and a dense aluminum fin array, Dark Rock 5 offers robust cooling. A special black coating with ceramic particles enables perfect heat transfer from the heat...
- The Silent Wings 4 120mm PWM fan features an advanced fluid-dynamic bearing, smooth 6-pole motor and airflow-optimized fan blades. Thanks to a tight tip clearance between fan blade and frame, the...
- The Dark Rock 5's asymmetrical design and heat sink cut-outs increase RAM and VRM cooler compatibility significantly and enable limitless memory height. Optionally, a second fan can be installed at...
The Dark Rock 5 is the single-tower sibling to the Pro 5. It offers a slightly better balance, providing extremely high cooling performance that still rivals many AIOs while offering improved compatibility with tall RAM and VRM heatsinks compared to its larger counterpart. It’s an ideal choice for the enthusiast who wants top-tier air cooling in a standard ATX or Micro-ATX case without the sheer bulk of a dual-tower design. Again, this cooler is for builders with ample space who are looking to quietly cool a powerful CPU, a completely different use case than the ultra-compact AXP90 X36.
3. ID-COOLING SE-224-XTS CPU Air Cooler
- 【Better Heat Dissipation】The CPU cooler comes with 4 heat pipes and 120mm PWM fan to make sure excellent heat transfer from CPU
- 【PWM Fan】The 120mm PWM fan delivers Low-Noise for automatic speed control and ultra-quiet operation for extreme CPU cooling performance. Max. Air Flow: 70CFM ; Noise Level: 28.9dB(A) Max
- 【RAM Compatibility】Non-interference with memory mounting even in mini-ITX motherboards due to the heatsink slant design
The ID-COOLING SE-224-XTS is a highly popular budget-oriented tower cooler. It represents a massive upgrade over most stock Intel and AMD coolers for a very reasonable price. With four heatpipes and a 120mm PWM fan, it provides excellent cooling for mainstream, non-overclocked CPUs. A builder would choose this if they are working in a standard case, want better-than-stock performance and acoustics without breaking the bank, and are using a mid-range processor. It offers fantastic value but, like the be quiet! coolers, it is far too large for the SFF environments where the Thermalright AXP90 X36 excels.
Our Final Verdict on the Thermalright AXP90 X36 Low Profile CPU Cooler 36mm
After extensive testing and analysis, our verdict is clear: the Thermalright AXP90 X36 Low Profile CPU Cooler 36mm is a specialized, high-performance tool that brilliantly executes its primary mission. It is, without a doubt, one of the best air coolers you can buy for builds where every single millimeter counts. Its ability to effectively cool mid-range processors like the Ryzen 5 series within a minuscule 36mm vertical footprint is nothing short of an engineering feat. The build quality is superb for its price point, and the cooling performance punches far above what its size would suggest.
However, it is not a product without flaws. The installation process is its Achilles’ heel, with confusing instructions and a back-mounted design that can be genuinely frustrating. The fan, while effective, will make its presence known under heavy load. We recommend this cooler specifically to patient and experienced SFF builders who understand the compromises inherent in compact builds and are willing to navigate a slightly tricky installation to achieve an incredibly clean, space-efficient, and well-cooled final product. For those brave builders, the reward is more than worth the effort. If you’re building in an ultra-slim chassis and need a cooler that delivers performance without the height, the Thermalright AXP90 X36 is an exceptional choice. You can get this game-changing SFF cooler for your build today.
Last update on 2025-11-07 / Affiliate links / Images from Amazon Product Advertising API