8 - Facts and noise levels
We are pretty specific with our reviews, so we look with keen interest at any aspect of the power supply. Some other observations & facts:
- Did you know that even with the PSU switch OFF, the PSU still consumes 25 Watt
- Did you know that with the PC off, yet the PSU switch on, this PC still consumed 32 Watt
- In Idle this overclocked system consumes 239 Watt with one GeForce 9800 GX2
- In Idle this overclocked system consumes 340 Watt with two GeForce 9800 GX2 cards
- The maximum peak we measured was 415 Watt with one GeForce 9800 GX2
- The maximum peak we measured was 631 Watt with two GeForce 9800 GX2 cards
With the PC powered down and the PSU switch off the PSU still still uses near 25 Watts. Why isn't off, really off with PSUs these days ??
Anyway, let's have a look at sound ... ehm, yeah, that's right.
Sound levels (dBA)
As usual we grabbed our dBa meter, enabled the PSU by hot-wiring it and started to listen if it made any significant noise. Short and simple it's really silent. With merely the PSU hotwired and no other electrical devices activated in a closed room we measured a dBA level of roughly 29 to 31 dBA. Yes correct ... that's just so hard to measure. It's nothing.
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.
All in all, extremely silent and thus highly recommended to any of the audiophiles that like silence (yours truly included). As always we measure ~75 CM away from the product (usually the distance between you and a desktop computer).
Quite honestly the Power Supply unit hotwired and activated, it is among the most silent PSUs we've ever tested. Very recommendable.
