Test Setup and Test Methodology

We are testing the noise level and performance of each fan at 3 different voltages (12/7/5);

For the noise tests we used a Velleman DVM1326 Sound Level Meter which reads from 35~130dB. We enabled A frequency weighing as this is resembles closest what the human ear hears. Ambient noise in the test room was 36.4dBA. We measured the noise of each fan mounted in a foam cutout construction to eliminate vibration noise. The dBA meter was placed outside the airflow path at ~5cm distance, the highest noise level at different voltages was recorded.

For the performance tests we used Pentium 4 system running underclocked at 2876Mhz, at higher CPU speeds we would get unstable temperatures with some of the lower RPM fans. We used a heatsink with a lot of small fins, the Scythe Zipang was our heatsink of choice for this particular test. The motherboard was placed outside a case on a cardboard box. Room temperature was 22.5°C during testing.

Intel S775 Setup
CPU	Pentium 4 524 @ 2876Mhz - 1.36v vcore
Mainboard	Asrock 775Dual-VSTA
Memory	1 * 512Mb Mushkin PC3200 LVLII V2
Other	Scythe Zipang ATI R9000 Passive Cooling FSP ZEN 400W Passive Cooled PSU Seagate 7200.8 200Gb HDD in Scythe Quiet Drive

From past experience we’ve noticed that while a dBA meter can give you a general idea of the noise level of a fan, it doesn’t necessarily make the difference between an “annoying” sound and a none-irritating frequency. With computer fans the source of an irritating noise is the motor, some bearings work very well when the fan is running at full speed but when less voltage is provided there’s a very irritating and audible motor noise present, instead of just the noise of air being moved by the fan blades. We placed every fan close to our ear and tried to gauge the “audible” level of the fan’s motor; we ranked fans which had an almost inaudible motor as “1”, if the motor noise was audible but none irritating it would get “2”, if the motor noise was quite noticeable, even from a distance, it would get a “3”, if the motor noise is irritating and really distracting a score of “4” was given.

To give you a practical example: the Coolink Breeze at 5v measured 41.1dBA at 5cm, Gelid Wing 12 measured 40.5dBA at the same distance. Performance of the Coolink: 49°C, Gelid: 51°C. If you were to base your buying decision on these two factors, you would go for the Coolink which offers a slightly better performance/noise balance. You get home install the fan, undervolt it 5v and be met with a very irritating buzzing noise coming from the fan motor. The dBA meter doesn’t tell us this, but our ears definitely perceive the Coolink fan as louder than the Gelid Wing 12.

On the next page we’ll try to display you all the results in a somewhat easy to read and understand chart. As well as an X/Y scatter chart, which does look nice, but with 30+ fans in the roundup is not very clear. To get things started, the raw results:


Click to Enlarge