TweakTown uses a different method for testing CPU heatsinks which allows for an even playing field across all product tests. We feel that by using the same ambient temperature and strict lab-like testing procedures we are able to accurately compare one product to another. More information on our testing procedure can be found in the T.E.C.C. article here.
The Noctua NH-U9B performed admirably against the competition with a better than average reporting of temperatures. Idling at a temperature of 55.4° and loading at a maximum temperature of 61.4° Celsius is not an easy feat to do with a 92mm fan powered CPU cooler. I have taken the lowest reading, of course, from the two fan configuration and used the hottest load temperature from the single fan to express this conclusion.
The sound pressure level testing was done as it is every time I test a cooler, but the NH-U9B really starts to express why this cooler is so nice to use day to day. At idle with a single fan (and dual fans for that matter), this cooler is virtually inaudible. Taking the cooler onward to the load testing, there it was again, one quiet cooler. With both fans running at maximum RPM, I only recorded a 56dB sound level reading, which if you look back to the NH-U12P, the NH-U9B is only 3dB louder. This is where Noctuas fan design really steps ahead. If they can keep smaller fans almost as quiet as their 120mm counterparts, I say they did one hell of a good job!