Gelid GX-7 CPU cooler review -
Noise levels - Sound pressure readings
With a certified dBA meter we measure how many dBAs originate from the PC. It's slightly subjective as there is always noise in the background, from the streets, from the HD, PSU fan, etc so this is by a mile or two not a precise measurement. You could only achieve objective measurement in a sound test chamber. Take this measurement as an indication, not a precise measurement please.
The human hearing system has different sensitivities at different frequencies. This means that the perception of noise is not at all equal at every frequency. Noise with significant measured levels (in dB) at high or low frequencies will not be as annoying as it would be when its energy is concentrated in the middle frequencies. In other words, the measured noise levels in dB will not reflect the actual human perception of the loudness of the noise. That's why we measure the dBA level. A specific circuit is added to the sound level meter to correct its reading in regard to this concept. This reading is the noise level in dBA. The letter A is added to indicate the correction that was made in the measurement. Frequencies below 1kHz and above 6kHz are attenuated, whereas frequencies between 1kHz and 6kHz are amplified by the A weighting.
|TYPICAL SOUND LEVELS|
|Jet takeoff (200 feet)||120 dBA|
|Construction Site||110 dBA||Intolerable|
|Shout (5 feet)||100 dBA|
|Heavy truck (50 feet)||90 dBA||Very noisy|
|Urban street||80 dBA|
|Automobile interior||70 dBA||Noisy|
|Normal conversation (3 feet)||60 dBA|
|Office, classroom||50 dBA||Moderate|
|Living room||40 dBA|
|Bedroom at night||30 dBA||Quiet|
|Broadcast studio||20 dBA|
|Rustling leaves||10 dBA||Barely audible|
But let's have a peek at noise levels. We take a dBA gun and point it at the working PC and take a distance of 75 CM. The PC again is stressed at 3200 MHz on the CPU with 80% RPM set in the BIOS. These, as such, are noise levels measured under heavy CPU load.
The GX-7 has two entries here, one and two fans. With one fan you'll measure roughly 43 dBA is normal to audible for your average PC. We find it a little on the high side.
If you need more cooling performance, then go for the 2nd fan. Mind you that it is loud and audible though.
Gelid is a company that made a nice impression a year or two ago introducing themselves by releasing their first aftermarket CPU cooler, the 'Silent Spirit' cooler. After Gelid released that Silent Spirit and then Tranqillo CPU coolers it was time for a new model. Progress is made and anno Q4 2011 it's time to release their third consumer grade CPU cooler. Their latest creation comes in the form of a tower cooler called GX-7 -- aimed at gamers apparently.