Load testing the PSU

Load testing the PSU

So during our tests we monitor the voltage fluctuations as shown above in both IDLE and LOAD states of the PC. We write down the lowest and highest value we see. That is the fluctuation, the baseline of the test. If a PSU is unstable we'd see much more fluctuation, differences and discrepancies which can result in system instability.

Once we collect all the results we can place them in an easy to understand chart. Look at the chart, the two lines show both the Idle and Load state of a specific voltage rail, the dark blue one the lowest voltage dip measured, the red one the highest fluctuation. That's your baseline.

So then, ATX specification requires that the PSU needs to stay within a 5% fluctuation, as such:

• 12 Volts should remain between 11.4 - 12.6v

As you can see the PSU when utilized stays FAR from that, meaning that the PSU is functioning within ATX specified limits. During the load test, I several times checked to see if the PSU was warm, it remained lukewarm at best. It almost feels like it's hardly doing anything at all. Another benefit there is that the fan RPM will remain low, and as such so will the airflow noise level coming from it.

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.

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.

How we test noise levels, (reference photo).

As always we measure 75 CM away from the product (usually the distance between you and a desktop computer), and yes... this test is always a tad subjective yet we measured 33~34 dBA (under ~700 Watt load) and that's including surrounding noise levels, that's just perfect. All in all, very silent and thus highly recommended to any of the audiophiles that like silence (yours truly included).