Performance

Testing methodology:
For idle temperatures the PC is run at idle for three hours and temperature is measured using Realtemp 3.4. For load temperatures Prime95 is run using the "In-place large FFTs" test for three hours then temperature is measured again with Realtemp. Ambient temperature was kept to 24° Celsius (+/- 1°C) and was measured by a standard mercury thermometer.

The system being used to test the heatsink is as follows:





In addition to testing on the test system, the NH-D14 was also tested on a Gigabyte X58A-UD3R with an Intel Xeon X5677 processor to see how well the cooler could perform with high overclocks that enthusiasts may reach. The Intel stock cooler while running the CPU, at a stock frequency of 3.6 GHz, held the CPU at 42°C under load, while the NH-D14 reached a a much lower 34°C. After a weekend of testing, the maximum overclock that was able to be achieved was 4.8 GHz with Hyper-Threading enabled and 1.42V to the CPU core. I was happy to see that the load temperature was no higher than 71°C on all four cores.

Fan Noise

Noctua is well known for their high quality silent fans. The NH-D14 comes with two fans, NF-P14 and NF-P12, the first being 140 mm and the latter being 120 mm. Both fans are extremely quiet at normal 12V operation, and both measure at 19 dB, but Noctua has gone the extra mile and included their Ultra-Low-Noise Adapters (U.L.N.A.) to reduce the fans' voltage down to 7V to further decrease fan noise. I found that at 12V the fans are both plenty quiet for my ears but die hard silence enthusiasts may want to make use of the included U.L.N.A. adapters for complete silence.