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 SilverStone SX700-G. 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 SilverStone SX700-G at 45c. This makes Test #1 equal to 184W by loading the 12v rail to 13a, the 5v rail to 2a, the 3.3v rail to 1a, the +5vsb to 2a, and the -12v to 0.3a. The SilverStone SX700-G is starting off in excellent shape. All of the rails we monitor 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 SilverStone SX700-G at 45c. This makes Test #2 equal to 325W 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 3.3v rail is coming in at ~15mV of ripple/noise, the 5v rail is coming in at less than ~10mV of ripple/noise, and the 12v rail is peaking at ~15mV of ripple/noise.

120v Input

100v Input

Test #3 is equal to approximately 75% of the rated capacity of SilverStone SX700-G at 45c. This makes Test #3 equal to 458W 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 ~15mV 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 SilverStone SX700-G at 45c. This makes Test #4 equal to 693W by loading the 12v rail to 56a, the 5v rail to 1a, the 3.3v rail to 1a, the +5vsb to 2a, and the -12v to 0.3a. In the final regular test, we see the 12v rail peaking at ~25mV of ripple/noise while the minor rails are peaking at ~20mV of ripple/noise on the 3.3v rail and ~10mV on the 5v rail.

Torture Test

The Torture Test is equal to approximately 80% of the rated capacity of the SilverStone SX700-G at 45C. This makes the Torture Test equal 570W by loading the 12v rail to 42a, 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 and 5v rails peaking at ~10mV of ripple/noise while the 3.3v rail is peaking at ~20mV of ripple/noise.

DC Output Quality Summary

The overall DC Output Quality of the SilverStone SX700-G is very good. The SX700-G ended up posting a peak trace amplitude on the 12v and 3.3v rails of ~20mV followed by ~10mV on the 5v rail. The worst relative value among these hit ~40% of the ATX12v specification limit and this unit was better than the FSP Dagger 600W. While that unit is not directly comparable because of the difference in capacity, it is the only other SFX unit we have seen to date and we would expect the larger unit to do worse than the smaller capacity unit. Let’s move on now and see how all of this wraps up!