To learn how we measure ripple, please click here.
The following table includes the ripple levels we measured on the EPF500AWT's rails. The limits, according to the ATX specification, are 120mV (+12V) and 50mV (5V, 3.3V and 5VSB).
Ripple suppression is satisfactory at +12V and pretty good at 5VSB. The minor rails fare well enough, but they really should be even better in such an expensive PSU.
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.