The following table includes the ripple levels we measured on CS850M’s rails. 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 on the minor rails is excellent, matching the performance of higher-end platforms built using much better components. However, while the initial performance of Taiwanese and Chinese capacitors may be good, what matters most is how they perform after a prolonged period. The caps in this unit are going to age much faster than Japanese caps.
Ripple suppression is decent on the +12V rail; we would prefer to see readings below 40mV during the full-load tests. Still, even some high-end PSUs register close to 40mV on this rail under worst-case conditions, so the CS850M's +12V ripple suppression can’t be characterized as bad or even mediocre.
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.