Testing and Results

We've included results from several CPU coolers in each test. Not all are present in all socket tests because some aren't compatible. In this case we've tried to include a similar cooler from that particular company.

Where CPU coolers had alternative fan speeds, we've tested at both the lowest and highest fan speed settings and recorded idle and load delta T results for each setting to give you some idea as to how much performance is affected.

We've also included the reference cooler for each socket which is a good indicator of what kind of improvement you'd see if in fact you're using the reference cooler. it also acts as a benchmark. For instance, you certainly wouldn't want to buy a cooler that performance worse than the reference cooler.

Delta T is the difference in °C between the ambient temperature and the recorded temperature of the hardware, in this case the CPU. We used Core Temp 0.99.4 to take temperature readings of the CPU from the Digital Thermal Sensor (DTS) embedded in the core of every modern CPU, at idle and under load while using the small FFT test in Prime 95.

A multimeter thermal attachment probe was used to take the ambient air temperature three inches away from the case's primary intake location. Delta T is a more accurate and comparable method of recording temperature because the ambient room temperature fluctuates from day to day.

For Socket AM2+ we used a 3GHz AMD Phenom II X4 940 Black Edition overclocked to 3.6GHz with the vcore boosted to 1.6V. Our LGA775 coolers had to contend with a 2.13GHz Xeon X3210 overclocked to 2.66 GHz by increasing its FSB from 266MHz to 333MHz and increasing the vcore to 1.41V.


While LGA1366 is the setup most people crave at the moment and LGA1156 is just around the corner, a vast majority of people have LGA775 systems. Core 2 CPUs are great overclockers combined with a good CPU cooler so if you're still using the reference cooler, the graph above shows that you can knock a sizeable amount off your CPU's idle and load temperatures. Unfortunately the NH-C12P didn't fare too well here even when using the fan at full speed, although it is notably quieter than the reference cooler.

It managed an idle delta T of 21°C, which is 3°C lower than the reference heatsink, but the even the Titan Fenrir at its lowest fan speed setting managed to knock a further 2°C off this with a delta T of 19°C.

Under load, the NH-C12P recorded an idle delta T of 49°C which is a mediocre 7°C lower than the reference cooler but again the Titan Fenrir was a further 7°C cooler at low speed, and a whopping 11°C cooler at full speed with an impressive delta T of just 38°C.

With the fan speed reduced to 900rpm, the idle delta T rose 2°C to 23°C and the load delta T rose to 54°C. This isn't much of a compromise and confirms our prediction that the widely spaced fins and potent fan mean that the NH-C12P is still a capable cooler at low fan speeds. However the reference cooler managed a load delta T of 56°C - just 2°C higher than the NH-C12P using the fan reduction cable. If your aim is for silence, then the Noctua at low fan speed clearly trumps the other coolers, but the Fenrir still gives it a severe thrashing in performance and value.


Socket AM2+ is a different story though and the NH-C12P is much better able to keep up with the likes of the Fenrir. With the fan at 1,300rpm it managed an idle delta T of 15°C which equalled the Fenrir at low fan speed an also the OCZ Vendetta 2. When we ramped up the load, it again matched the Vendetta 2 and Fenrir at low fan speed with a delta T of 37°C which is a healthy 9°C lower than the reference cooler.

When we added the fan speed reduction cable the idle delta T rose 4°C to 19°C but this was still 3°C lower than the reference cooler. The load delta T rose just 2°C to 39°C which is impressive as it means you can run the fan at some pretty low revs, and still get performance that treads all over the reference cooler both at idle and load. As the NH-C12P is compatible with AMD AM3 out of the box, it's a definite contender for a top spot on your list of CPU coolers.