DC Output Quality
For those of you that are curious as to some of the reasoning, equipment, and how our rating system works behind our PSU testing program here at TheFPSReview, we have put together an introduction for you. This program is based on what the author developed at [H]ardOCP and utilizes the equipment bequeathed to the author by Kyle Bennett. The testing we are conducting today is exactly as described in that document and will continue with our examination of the DC Output Quality.
Control Test Graphing
This image is the blank background control test on an unused connector from our SM-8800 during the testing of the Cooler Master XG PLUS 850 Platinum. This lets us determine what the background noise looks like during testing.
120v Input
100v Input
Test #1 is equal to approximately 25% of the rated capacity of the Cooler Master XG PLUS 850 Platinum at 45c. This makes Test #1 equal to 220W by loading the 12v rail to 16a, the 5v rail to 2a, the 3.3v rail to 1a, the +5vsb to 2a, and the -12v to 0.3a. The XG PLUS 850 Platinum is starting off very stable. The 12v, 5v, and 3.3v rails rail is peaking at less than ~10mV of ripple/noise.
120v Input
100v Input
Test #2 is equal to approximately 50% of the rated capacity of the Cooler Master XG PLUS 850 Platinum at 45c. This makes Test #2 equal to 430W by loading the 12v rail to 32a, the 5v rail to 4a, the 3.3v rail to 3a, the +5vsb to 2a, and the -12v to 0.3a. Test #2 sees some change as the 12v rail is coming in at ~20mV of ripple/noise and the minor rails are coming in at ~10mV of ripple/noise.
120v Input
100v Input
Test #3 is equal to approximately 75% of the rated capacity of Cooler Master XG PLUS 850 Platinum at 45c. This makes Test #3 equal to 635W by loading the 12v rail to 48a, the 5v rail to 6a, the 3.3v rail to 4a, the +5vsb to 2a, and the -12v to 0.3a. Test #3 sees the 12v rail peaking at ~25mV of ripple/noise while the minor rails are coming in at ~10mV of ripple/noise or less.
120v Input
100v Input
Test #4 is equal to approximately 100% of the rated capacity of the Cooler Master XG PLUS 850 Platinum at 45c. This makes Test #4 equal to 848W by loading the 12v rail to 68a, the 5v rail to 2a, the 3.3v rail to 2a, the +5vsb to 2a, and the -12v to 0.3a. In the final regular test, we see the 12v rail peaking at ~35mV of ripple/noise while the minor rails are peaking at ~15mV of ripple/noise.
Torture Test
The Torture Test is equal to approximately 80% of the rated capacity of the Cooler Master XG PLUS 850 Platinum at 45C. This makes the Torture Test equal to 668W by loading the 12v rail to 50a, the 5v rail to 7a, the 3.3v rail to 5a, the +5vsb to 2a, and the -12v to 0.3a. At the end of the Torture Test, we see the 12v rail peaking at ~30mV of ripple/noise while the minor rails are peaking at ~15mV of ripple/noise (3.3v) or ~10mV of ripple/noise (5v).
DC Output Quality Summary
The overall DC Output Quality of the Cooler Master XG PLUS 850 Platinum is very good in an absolute sense! The XG PLUS 850 Platinum ended up posting a peak trace amplitude on the 12v rail of ~35mV followed by ~15mV on the 5v and 3.3v rails. The worst relative value among these was the 12v rail hit well below ~50% of the ATX12v specification limit the minor rails did even better!
However, these results are slightly trailing the SilverStone DA850 Gold, MSI A850GF, ASUS ROG THOR 850W, and the Enermax REVOLUTION DF 850W. So, while the absolute values are very good in this aspect, this unit is just ever so slightly off the pace of the leaders we have seen to date. Let’s move on now and see how all of this wraps up!