Testing Methodology

To actually test these fans in the wild, we built two systems using identical components except for the cases utilized. We also limited our real-world testing to the 120mm model. Believe it or not we had no cases available that even took an 80mm fan. The systems consisted of the following common components...

• Intel Core 2 E6300 CPU
• Arctic Freezer7 Pro Heatsink
• ECS PX1 Intel P965 Mainboard
• 2x1GB Crucial Ballistic DDR2-1000 Memory modules
• Seagate ST3120026AS 120GB SATA HDD
• Liteon 165P6S DVD-RW Drive
• Crucial ATI X1600XT 256MB PCI-E Video Card

The area where we differentiated things was in the cases used. We used two very different cases to test these fans in. First, a Rosewill R6A34-BK case, which comes stock with one 120mm Yate Loon D12SH-12 case fan in the front of the case. Secondly a Coolermaster Mystique case, which comes with two of its own Coolermaster R4-L2S-122B-GP fans. To be fair, since we only had one Noctua NF-S12 fan to play with, we removed the rear fan from the Mystique case. We also utilized different PSU's in each case, with the Rosewill case sporting Airnet APS500w PSU with an 80mm exhaust fan, and the Coolermaster case using a Coolermaster iGreen RS-600 PSU which incorporates a 130mm exhaust fan.

Our methodology was rather simple. We utilized an old Radio Shack SPL meter (from our managing editors days tuning parametric equalizers and crossovers in his car-stereo crazy days), mounted on a tripod and aimed at each case from a distance of one meter. We then did a simple measurement of sound pressure level (dB, A-Weighted scale) comparing acoustic characteristics to the stock fans that came in each case. We did try additional thermal tests, comparing changes in case temperature between the fans, but considering the similar CFM characteristics involved, we saw no real differences in case temperature.

In the case of the Rosewill case, we had a much louder front case fan. The Airnet APS500 PSU was also subjectively a little louder than the Coolermaster's iGreen RS-600 PSU. Simply changing out the front fan from the Yate Loon model to the Noctua NF-S12 made a huge difference in measured sound pressure level. Even with a 40cfm deficit in airflow to the Yate Loon we saw no significant difference in case temperatures either, though admittedly this wasn't an extreme system build either.

With the Coolermaster case, we already had a rather quiet low speed case fan, and the Coolermaster iGreen RS-600 PSU itself is also designed for quiet operation. Still with the Noctua NF-S12 fan installed it was significantly quieter, to the tune of 5dB. Sporting a tiny bit more in the way of CFM than Coolermaster's own case fan, we still saw no appreciable gains or losses in case temperature.

Subjectively, not only did the Noctua NF-S12 come out of the tests as much quieter to the meter, they came out to our ears as even quieter than the tests would indicate. It's clearly a guess, but we feel Noctua tuned the acoustic profiles of these fans to fall within noise ranges that most resemble the background noise we tend to not notice in the first place. With the fan off, you can clearly tell the difference in noise profile. Replugging the fan and subjectively listening though, one would be hard pressed to localize the sound being generated by the fan.

With that it's time to wrap things up.