Noise Levels and Fan Speeds
Testing ProcedureFan noise testing is done at 25%, 50%, and 100% fan speed, with the dBA level being recorded by a Pyle PSPL25 sound pressure level meter at a distance of 30 cm. The fan(s) RPM results are taken at the same 25%, 50%, and 100% settings. The selected speeds are handled by MSI's Command Center software, and a Lamptron FC6 fan controller is also used as a secondary method of confirming RPM and dBA readings in case MSI's Command Center cannot control the fan(s), which ensures that proper results can still be obtained if the software fails. To give users the noise profile of the tested CPU cooler, testing is done using fan speed percentages instead of various load levels.
Noctua again lives up to the hype by offering a near-silent experience. While not on the same level as be quiet! and their Dark Rock Pro 3, Noctua still does well at maximum fan speed as a reading of 43 dBA is just 3 dBA behind the quietest coolers tested. With the cooler only 1-2 dBA behind the quietest coolers, Noctua does extremely well at 25% and 50% fan speed. This is why Noctua has the reputation it does. Not only does the NH-D15 take the air-cooling crown, it does so while being extremely quiet.
RPM readings show why the NH-D15 manages to have such a quiet noise profile. At 25%, its fans only spin at 421 RPM, and 837 RPM at 50%. Staying below 1000 RPM nearly makes it a dead-silent cooling solution, and although the 1521 RPM the fans max out at produces a hum, you will not hear the fans once the cooler is inside a case. Its top quality fans really make this CPU cooler shine.