To learn how we measure ripple, please click here.
The following table includes the ripple levels we measured on the XTR 850W's rails. The limits, according to the ATX specification, are 120mV (+12V) and 50mV (5V, 3.3V and 5VSB).
Ripple suppression on the minor rails is very good. We could easily praise the +12V rail's performance as well, if we hadn't already seen the EVGA G2/P2 and Corsair RMx and RMi units, which set the bar too high in this section. Under no circumstances can you call 33mV of ripple under full load a mediocre performance, that's for sure. However, when you have measured below 15mV under the same conditions in other PSUs, you have no other option but to expect more from an OEM like Seasonic.
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.