To learn how we measure ripple, please click here.
The following table includes the ripple levels we measured on the SDA600's rails. The limits, according to the ATX specification, are 120mV (+12V) and 50mV (5V, 3.3V and 5VSB).
It looks like FSP paid great attention to ripple suppression at +12V (the most important rail), but totally ignored the 3.3V rail. From the 70% load test and beyond, it goes out of control.
We're disappointed to see a high-end SFX unit unable to keep its ripple within the ATX spec's limits, which are already set very high. We had a couple of SDA600s in our possession, so we tested both of them to check for a possible bad sample. Unfortunately, the second unit's performance was identical. That means the 3.3V module has a problem FSP needs to fix.
Ripple Oscilloscope Screenshots
The following oscilloscope screenshots illustrate the AC ripple and noise registered on the main rails (+12V, 5V, 3.3V and 5VSB). The bigger the fluctuations on the screen, the bigger the ripple/noise. We set 0.01 V/Div (each vertical division/box equals 0.01V) as the standard for all measurements.
Ripple At Full Load
Ripple At 110-Percent Load
Ripple At Cross-Load 1
Ripple At Cross-Load 2
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