DC Output Quality
For those of you that are curious as to some of the reasoning and equipment behind our PSU testing program here at TheFPSReview, we have put together an introduction for you that shares a lot of the behind the scenes of the program. 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 Seasonic FOCUS GM-650. 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 Seasonic FOCUS GM-650 at 45c. This makes Test #1 equal to 171W by loading the 12v rail to 12a, the 5v rail to 2a, the 3.3v rail to 1a, the +5vsb to 2a, and the -12v to 0.3a. The FOCUS GM-650 is starting off in mixed shape. The 12v rail is peaking at ~25mV of ripple/noise and the minor rails are 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 Seasonic FOCUS GM-650 at 45c. This makes Test #2 equal to 322W by loading the 12v rail to 24a, the 5v rail to 3a, the 3.3v rail to 2a, the +5vsb to 2a, and the -12v to 0.3a. Test #2 sees only minor changes as the 12v rail is coming in at ~40mV of ripple/noise and the minor rails are coming in at less than ~10mV of ripple/noise.
120v Input
100v Input
Test #3 is equal to approximately 75% of the rated capacity of Seasonic FOCUS GM-650 at 45c. This makes Test #3 equal to 482W by loading the 12v rail to 36a, the 5v rail to 5a, the 3.3v rail to 4a, the +5vsb to 2a, and the -12v to 0.3a. Test #3 sees the 12v rail peaking at ~30mV of ripple/noise while the minor rails are coming in at ~10mV of ripple/noise.
120v Input
100v Input
Test #4 is equal to approximately 100% of the rated capacity of the Seasonic FOCUS GM-650 at 45c. This makes Test #4 equal to 644W by loading the 12v rail to 50a, the 5v rail to 5a, the 3.3v rail to 3a, the +5vsb to 2a, and the -12v to 0.3a. In the final regular test, we see the 12v rail peaking at ~40mV of ripple/noise while the minor rails are peaking at ~10mV of ripple/noise.
Torture Test
The Torture Test is equal to approximately 80% of the rated capacity of the Seasonic FOCUS GM-650 at 45C. This makes the Torture Test equal to 513W by loading the 12v rail to 38a, 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 ~10mV of ripple/noise.
DC Output Quality Summary
The overall DC Output Quality of the Seasonic FOCUS GM-650 is very good to excellent! The FOCUS GM-650 ended up posting a peak trace amplitude on the 12v rail of ~40mV followed by ~10mV on the 5v rail and ~10mV on the 3.3v rail during our normal tests. The worst relative value among these hit well below ~50% of the ATX12v specification limit and this was on the 12v rail. The minor rails did even better! So, while we do not have other 650W units to compare to, it seems based on raw numbers that this unit is going to be among the best midrange 650W units on the market! Let’s move on now and see how all of this wraps up!