- Review -

09.02.2015 VRWorld.com

In terms of noise levels, both the NH-D9L and the NH-U9S are barely audible when idling. One of Noctua’s main strengths is in designing CPU coolers that are quiet, and thanks to the newer NF-A9 fan, there was barely any audible sound from the cooler when idling. Under load, the NH-U9S came in at 41 degrees Celsius, and after running OCCT for over ten minutes, the cooler registered a maximum temperature of 62.5 degrees Celsius. Sound levels never exceeded 42.1 dBA even under full load. Adding a second fan to the mix served to reduce the temperature to another two degrees Celsius while increasing the sound levels by as much as 1.5 to 2 dBA. The NH-D9L is similarly quiet, registering sound levels of a maximum of 41.2 dBA under full load and a temperature maximum of 62 degrees.

"Noctua has successfully managed to achieve a similar amount of efficiency with the NH-U9S and the NH-D9L as their larger-sized brethren. With the NH-U9S, changes in design and addition of a heatpipe have allowed the cooler to work at the same level as the NH-U9B SE2 with a single fan. What we have here with the NH-D9L is essentially a smaller NH-D15, which is great seeing as how the latter is considered to be one of the best CPU coolers available." (Harish Jonnalagadda, VRWorld.com)