This article was updated on June 17, 2021 to show equalized graph settings (i.e. minimum 50, maximum 70) in benchmarks except for Cinbench R23 & AIDA64 (which ran above 70)
This article was updated on June 20, 2021 to include data showing clockspeeds maintained while running Cinbench R23 and AIDA64.
Parts used for this review
| Cooler | Scythe Fuma 2 CPU Cooler (sent by Scythe) |
| Comparison Cooler | Noctua NH-U12S |
| Thermal Paste | Noctua NT-H1 |
| CPU | Intel i9 10900K (sent by Intel) |
| Motherboard | ASRock b560 Steel Legend (sent by ASRock, previously reviewed here) |
| Computer Case | NZXT H440 |
Today we’ll be looking at Scythe’s Fuma 2 CPU Cooler, a mid-range CPU Cooler that typically retails for $60 USD. First we’ll take look at the official specifications of this product.
Cooler Specifications
| Cooler | Scythe FUMA 2 |
| Height | 154.5mm / 6.08″ (including fans) |
| Width | 137mm / 5.39″ (including fans) |
| Depth | 131mm / 5.16″ (including fans) |
| Weight | 1000g/33.8oz (including fans) |
| Fan Compatibility | 120×120 |
| TDP (our estimate) | <200W |
| Warranty | 2 years |
| Price (Amazon.com) | $59.99 |
Fan Specifications
There’s more to a cooler than just it’s heat sink. The fans included have a huge impact on cooling performance and noise levels. Included with the FUMA 2 are the Kaze Flex 120 PWM and the Kaze Flex 120 Slim PWM fans.
| Fan 1 | Kaze Flex 120 Slim PWM – 1200 RPM |
| Size | 120 x 120 x 17 mm |
| Fan Speed | 300 ± 200 ~ 1200 ± 10% RPM |
| Air Flow | 8.28 ~ 33.86 CFM |
| Static Pressure | 0.056 ~ 0.9 mmH20 |
| Noise | 2.7 ~ 23.9 dBA |
| Voltage range | 12 V |
| MTTF | > 120,000 Hours |
| Fan 2 | Kaze Flex 120 PWM – 1200 RPM |
| Size | 120 x 120 x 27 mm |
| Fan Speed | 300 ± 200 ~ 1200 ± 10% RPM |
| Air Flow | 16.6 ~ 51.17 CFM |
| Static Pressure | 0.0762 ~ 1.05 mmH20 |
| Noise | 4 ~ 24.9 dBA |
| Voltage range | 12 V |
| MTTF | > 120,000 Hours |
In addition to the heat sink and fans, Scythe also includes thermal paste, a screwdriver, and additional fan clips so that you can install a 3rd fan for increased cooling performance if desired,.
Installing the FUMA 2
Installation of the FUMA 2 was fairly simple. Press the back plate against the motherboard, insert the stand-offs on the opposite side, attach and screw in the mounting brackets, and finally attach and screw in the heat sink – and then add the included fans. Scythe has advised that when installing the heat sink to only push the screws to the point of resistance.
Testing Methodology
I tested both the Noctua NH-U12S and the Scythe FUMA 2 in my home’s computer room with central air set to 73F. Both coolers were tested using Noctua NT-H1 thermal paste.
I tested each cooler with unlimited power limits and an enforced 100w TDP (to simulate an overclocked 65w CPU, such as AMD’s Ryzen 5 5600x) using both the “standard” and “full speed” profiles available from my motherboard.
Prior to testing at each TDP level, I would run AIDA64 CPU & FPU Stability test for one hour to soak the room with the heat generated from the CPU to ensure consistency in results.
Acoustics
The FUMA 2 is the quietest CPU cooler I have tested thus far. No matter the fan speed set, I was unable to discern the sound of the CPU cooler over the sound of the other fans in my case. In comparison, I was able to tell whenever the fan on the Noctua NH-U12S kicked in.
100w TDP Testing
The first tests were done with a TDP enforced at a 100w limit, because most consumers considering this cooler will likely be using a mid-range CPU like the Ryzen 5 3600x. Both coolers performed on par with each other – with the FUMA 2 winning some tests by a small margin, and the NH-U12S winning other tests by a small margin.
When switching to the “Full Speed” fan profile, both coolers see improvements – but the Noctua saw better improvements, resulting in it outperforming the FUMA 2 by a small margin. However, it did so at the cost of a higher noise level – whereas I couldn’t tell the difference in noise level using the FUMA 2.
No Power Limits Testing
I also wanted to see how the FUMA 2 performed with a space heater under extreme conditions. In order to see how much it could really handle, I tested it with the i9-10900k – the hardest consumer CPU to cool on the market – with no power limits.
In AIDA 64, both coolers thermal throttled with a CPU power consumption of just under 200w. The Noctua held slightly higher clock speeds, with 4803mhz vs 4745mhz.
In Cinebench R23, we see both coolers causing the CPU to throttle due to thermals again. The NH-U12S lead here by a small margin (about 1% faster), maintaining an average of 4826mhz with the CPU consuming 221w of electricity in full speed fan testing. The FUMA 2 maintained an average of 4773mhz with the CPU pulling 207w of electricity.
Conclusion
The fans included with the Scythe FUMA 2 have both pros and cons. Because the included fans are low RPM, no matter what setting I used for fan speeds I was unable to discern the sound of the CPU fans from the rest of the computer, which will be appreciated by those who want a quiet build.
On the flip side, the low RPMs are also limiting the potential performance of this cooler – I imagine this cooler would perform better with higher RPM fans. I’ll be exploring this further and testing the FUMA 2 (and other coolers) with upgraded fans in a future article.
I definitely recommend the Scythe FUMA 2 over the Noctua NH-U12 because it is a better value and cheaper at $60 USD, it is *much* quieter, and also has better upgrade options due to having 3 slots where one can attach a 120mm cooler.
