9-Way 850W Power Supply Roundup

Voltage Regulation

Varying load scenarios have different impacts upon voltage regulation which is why we test the regulation on both the CPU and a PCI-E connectors. To do this, we use a “loaded” connector which is installed and insert the multimeter’s probe into the back.


+12V PCI-E Voltage


Considering the load we are putting these units under, it is great to see that so many of them did well in this test. However, there were two exceptions with the Ultra X4 and the Cooler Master unit returning what we consider slightly disappointing results but for entirely different reasons. The Ultra may be well within the ATX specified limits but in our opinion, it plays its game far too close to the maximum allowable 12.60V. We have to remember that the larger the delta between the highest and lowest voltage, the more the VRMs on your GPU or CPU have to work and with a delta of about 0.40V, things don’t look good for the Ultra unit. The Cooler Master on the other hand returns disappointing results by having its voltage tank but it did manage to stay above the ATX specified minimum.


+12V CPU Voltage


Since all of these units are basically based off of single rail designs and the separate “rails” are derived from current limiters, it isn’t surprising that these results closely reflect those of the last test. The Ultra unit does actually do quite a bit better here which could be due to anything from modular interface soldering joints causing the drops in the PCI-E test to the load on that specific connector. That isn’t to say that we were impressed with its results since like the Cooler Master, the voltage fluctuations were a bit too much for our liking.


A Note About +3.3V / +5V Regulation

As was stated in the methodology section, all of the +3.3V and +5V voltages were recorded but there was next to no variance so a chart here would be nothing but filler. Honestly, a modern PC system hardly uses either of these rails and to focus too much on them is simply a waste of time in our books.