To learn how we measure ripple, please click here.
The following table includes the ripple levels we measured on the rails of the P11-850. The limits are, according to the ATX specification, 120mV (+12V) and 50mV (5V, 3.3V and 5VSB).
|Test||12V (mV)||5V (mV)||3.3V (mV)||5VSB (mV)||Pass/Fail|
Ripple suppression was superb at +12V and at good levels on the minor rails. The only rail that went above 20mV was the 5VSB rail. However, ripple suppression isn’t so crucial on this rail, since it is mostly used for charging various devices. And the ripple that registered was still much lower than the 50mV limit that the ATX spec sets.
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 0.01V/Div (each vertical division/box equals 0.01V) as the standard for all measurements.