A recent look at ASRock's M8 compact barebones PC saw us undervolting our CPU in order to run stably, overclocked. This forced us to ask the question: how much cooling can we fit inside a slim enclosure? Eight heat sink vendors helped us find the answer.
Compact enthusiast-oriented PCs are becoming increasingly popular as hardware vendors improve the efficiency of their components alongside raw performance. In the last year, we've covered complete mini-ITX systems, low-profile memory kits, and small enclosures. We even based an entire System Builder Marathon on the mini-ITX form factor.
One thing we found during that exercise was that it's difficult to match the dimensions of boutique-built boxes with high-end hardware, if only because there aren't many enclosures optimized for tiny spaces and big specs. Always eager to make bold statements of frugality, I came upon ASRock’s M8 mini barebones system, to which I added a number fairly potent parts. I then ran smack up against the reason that Chris paid big bucks for his Tiki: ASRock’s M8 wasn’t designed for high-performance CPU cooling. The best I could do was 4 GHz, and that was only after I reconfigured the barebones machine's intake and exhaust fans, upgraded the CPU cooler, and locked the processor's core voltage at a level below Intel's stock ceiling. Clearly there was room for improvement.
We set our upper limit for cooler size at 4” to cover the largest of slim cases, and eight different heat sink vendors responded with samples. Six of them even fit within the approximate 3” limit of ASRock’s M8. One manufacturer said it thought its submission would qualify, but might not fit our test motherboard (even though we were sure it would). Several others asked us for a few additional millimeters of headroom, though that would have resulted in a viscous cycle. It was important to us that we keep this a comparison of truly low-profile coolers to address the growing compact computing market.
Here are today’s contenders:

| Low-Profile CPU Cooler Features | ||||
|---|---|---|---|---|
| Gamer Storm Gabriel | Noctua NH-L12 | Scythe Big Shuriken 2 Rev. B | SilenX EFZ-100HA2 | |
| Height | 2.4" | 3.7" | 2.3" | 2.2" |
| Width | 4.8" | 5.8" | 5.3" | 4.7" |
| Depth | 4.8" | 5.3" | 4.9" | 4.8" |
| Base Height | 1.1" | 1.6" | 1.4" | 0.8-1.5" Tapered |
| Assy. Offset | 0.6" x 0.5" | 0.5" | None | None |
| Cooling Fans | (1) 120 x15 mm | (1) 120 x25 mm, (1) 92 x25 mm | (1) 120 x12 mm | (1) 92 x15 mm |
| Connectors | (1) PWM | (2) PWM | (1) PWM | (1) Three-Pin |
| Weight | 14 Ounces | 24 Ounces | 17 Ounces | Eight Ounces |
| Intel Sockets | 115x (1150/1155/1156) | 115x, 2011, 1366, 775 | 115x, 2011, 1366, 775 | 115x, 775 |
| AMD Sockets | Four-bolt Rectangular | Four-bolt Rectangular | All Four/Two-bolt | All Clip-On |
| Warranty | One Year | Six Years | Two Years | Three Years |
| Web Price | (Not Available in UK) | £50 | £40 | £15 |
Due to distribution issues, the Gabriel CPU cooler’s price is an estimate based on the company’s other products. That doesn’t leave any room for award recognition, but it still lets us get a look at performance in lieu of its final release. Noctua’s NH-L12 is distinct in that it's the largest cooler to qualify for our story.

| Low-Profile CPU Cooler Features | ||||
|---|---|---|---|---|
| SilverStone Nitrogon NT06-Pro | Thermalright AXP-200R | Xigmatek Janus | Zalman CNPS8900 Quiet | |
| Height | 3.2" | 2.8" | 2.5" | 2.4" |
| Width | 5.5" | 6.0" | 4.7" | 4.7" |
| Depth | 5.5" | 5.4" | 4.7" | 4.7" |
| Base Height | 1.2" (w/fan) | 1.4" | 1.2" | 1.3" |
| Assy. Offset | 0.8" (x) | 1.1" (x) | 0.6" | None |
| Cooling Fans | (1) 120 x20 mm | (1) 140 x13 mm | (1) 120 x15 mm (1) 80 x10 mm | (1) 110 x25 mm |
| Connectors | (1) PWM | (1) PWM | (1) PWM (1) Three-Pin | (1) PWM |
| Weight | 23 Ounces | 24 Ounces | 15 Ounces | 14 Ounces |
| Intel Sockets | 115x, 2011, 1366, 775 | 115x, 2011, 1366, 775 | 115x, 2011, 1366, 775 | 115x, 1366, 775 |
| AMD Sockets | Four-bolt Rectangular | All Four/Two-bolt | Four-bolt Rectangular | Four-bolt Rectangular |
| Warranty | One Year | One Year | One Year | One Year |
| Web Price | £55 | £50 | (Not Available in UK) | £30 |
Thermalright’s special-edition AXP-200R is similarly estimated to cost slightly more than the AXP-200. Both coolers are identical apart from fan color, though we aren't worried about value judgements on a product that sells for at least £47. On the other hand, exceptional performance could open the door to Tom's Hardware Elite recognition, regardless of price.
Designed to support two fans in a push-pull configuration, SilverStone’s NT06-Pro includes only one. The firm instructs users of low-profile cases to mount the fan below its radiator, so that’s how we're testing it. It might even squeeze into ASRock’s M8 in this configuration, though the side panel would probably block airflow through its fins.
- Eight Low-Profile Heat Sinks For Your Compact PC
- Gamer Storm Gabriel
- Gabriel Installation
- Noctua NH-L12
- NH-L12 Installation
- Scythe Big Shuriken 2 Revision B
- Big Shuriken 2 Revision B Installation
- SilenX EFZ-100HA2
- EFZ-100HA2 Installation
- SilverStone Nitrogon NT06-Pro
- Nitrogon NT06-Pro Installation
- Thermalright AXP-200 And AXP-200R
- AXP-200R Installation
- Xigmatek Janus
- Janus Installation
- Zalman CNPS8900 Quiet
- CNPS8900 Quiet Installation
- Test Settings And Methodology
- Results: Cooling And Fan Speed
- Results: Noise And Acoustic Efficiency
- Cooling Value
- The Best Cooler For Compact Systems?
Nocturna NH-L12 is best quality (Don't forgot about 6 ears of warranty)
and Zalman CNPS8900 Quiet Smart Buy
Also the NH-L12 I believe is compatible with Noctua's NF-A15 which is a 150mm PWM fan with 120mm mounting holes. In my perfect small form factor case I'd swap one of those as the top fan and just use a 150mm side vent as the only exhaust for the case, with other vents as intakes over the major components, or maybe leave off the top fan in favour of fitting an 200mm fan if space allows. That being for a high performance small case anyway, anything more modest I'd probably just go for the 37mm option.
Another favourite option is Prolimatech's Samuel 17 cool (45mm) plus one of their 140mm x 15mm Ultra Sleek Vortex fans for a total height of ~60mm, which still tops out under 2.5"