Stability Testing the PSU
Stability testing the PSU
So, during our tests we also monitor the voltage fluctuations as shown below in both IDLE and LOAD states of the PC. We write down the lowest and highest value we see within a certain PC state. The difference is the fluctuation. If a PSU is unstable we'd see a lot of fluctuation, differences and discrepancies which can result in system instability.
Once we gathered all voltage 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 stays within a 5% fluctuation; for example, each +12 volt rail should remain between 11.4 - 12.6 volts.
As you can see, the PSU when utilized stays consistent as you can hardly even see the blue line, meaning the PSU is functioning within ATX specified limits. During the load test, I checked several times to see if the PSU was warm, it was cold to lukewarm really.
We have not seen a PSU with high or low voltage dips in the last two years to be honest.
Testing with four GPUs
Since this is a 1000W PSU we could not leave you guys hanging dry. We in fact installed a second GeForce GTX 590 to see the power draw. You'll notice that four GPUs will stress the power supply more, we peak at 754 watts.
This is merely a demonstration test that shows the total wattage in the different tested modes. With four GPUs, during gaming we peak at a whopping 754W, granted that could have been worse but sure, could also have been a notch better. Only Platinum certified power supplies will shave off another 15, maybe 30 watts in the Metro game test. The efficiency of this product seems rock solid and very close to advertised standards.