Transient Testing
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 Transient Testing.
Transient Test 1
Loaded/Unloaded



12v/5v


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 before the addition of the transient load. The results of Test #1 show a ~330mV drop on the 12v rail and ~40mV drop on the 5v rail when each is directly loaded. At the same time that the load was being triggered on the 12v rail, the 5v rail measured a ~35mV drop.
Transient Test 2
Loaded/Unloaded



12v/5v


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 before the addition of the transient load. The results of Test #2 show a ~305mV drop on the 12v rail and ~40mV drop on the 5v rail when each is directly loaded. At the same time that the load was being triggered on the 12v rail, the 5v rail measured a ~35mV drop.
Transient Load Testing Summary
The Transient Load Test results for the Cooler Master XG PLUS 850 Platinum are passing. In today’s testing, the XG PLUS 850 Platinum saw the loaded 12v rail post a peak change of ~330mV and the loaded 5v rail post a peak change of ~40mV. The unloaded 5v peak change during the 12v load was ~35mV. Those numbers are, in an absolute sense, passing. In a relative sense, this unit is better than the SilverStone DA850 Gold and MSI A850GF while being mixed with the ASUS ROG THOR 850W and Enermax REVOLUTION DF 850W. Thus, this unit is definitely competitive with the best units we have seen in this regard. Let’s move on now to see how this unit does in the DC Output Quality aspect of our testing!

Discussion (6 replies)
Join Discussion →Paul's back in the house!
Shouldn't it actually be called the Colormaster? Just sayin' based on the box images.
They do like their RGB boxes.
I'm personally very glad to see more platnium and up power supplies being reviewed here. The vast quantity of 80plus gold PS's being used for high power situations is wasteful in my opinion and harder on your home solutions than it is worth.
Platinum or higher rated PS's especially in the 1kplus arena are giving you more life out of your UPS, your Power outlets, and your breakers in your home. And many of them helps improve impact on the grid at large too.
I'm still not sold that the ratings are all that meaningful.
I mean - yeah, taken at face value - they totally are. But I guess I doubt that many actually live up to their rating.
Which is why we have reviews and testing. Sites like the FPS review and others that actually put power supplies and other products through their paces to make sure they equal or exceed what the published ratings say. And not just with golden samples sent to them.