Performance

Testing methodology:
For idle temperatures the PC is run at idle for one hour and temperature is measured using Realtemp 3.4. For load temperatures Prime95 is run using the "In-place large FFTs" test for one hour then temperature is measured again with Realtemp. Ambient temperature was kept to 20° Celsius (+/- 1°C) and was measured by a standard mercury thermometer.

The system being used to test the heatsink is as follows:
**NOTE: All coolers used in the following graphs were retested for this review.

Fan Noise

Noctua is well known for their high quality silent fans. The NH-U9B SE2 comes with two Noctua NF-B9 fans which are 92 mm in size. The fans are extremely quiet during normal 12V operation, and measure at 17.6 dB, but Noctua has gone the extra mile and included their Ultra-Low-Noise Adapters (U.L.N.A.) and Low-Noise Adapters (L.N.A.) to reduce the fans' voltage down to 5V or 7V to further decrease fan noise. I found that at 12V the fans are plenty quiet for my ears but die hard silence enthusiasts may want to make use of the included U.L.N.A. or L.N.A adapters for complete silence.