Ripple Measurements
To learn how we measure ripple, please click here.
The following table includes the ripple levels we measured on the GX-F750's rails. The limits, according to the ATX specification, are 120mV (+12V) and 50mV (5V, 3.3V, and 5VSB).
| Test | 12V | 5V | 3.3V | 5VSB | Pass/Fail |
|---|---|---|---|---|---|
| 10% Load | 8.4mV | 7.9mV | 9.1mV | 7.7mV | Pass |
| 20% Load | 7.5mV | 8.4mV | 10.1mV | 9.7mV | Pass |
| 30% Load | 7.9mV | 8.6mV | 11.0mV | 10.8mV | Pass |
| 40% Load | 8.3mV | 8.8mV | 12.3mV | 12.3mV | Pass |
| 50% Load | 8.6mV | 9.2mV | 14.9mV | 13.8mV | Pass |
| 60% Load | 9.0mV | 10.6mV | 14.8mV | 15.4mV | Pass |
| 70% Load | 9.3mV | 10.8mV | 16.1mV | 17.3mV | Pass |
| 80% Load | 9.3mV | 11.4mV | 17.3mV | 19.9mV | Pass |
| 90% Load | 10.0mV | 11.8mV | 18.5mV | 21.1mV | Pass |
| 100% Load | 10.7mV | 14.4mV | 22.7mV | 24.6mV | Pass |
| 110% Load | 11.9mV | 17.1mV | 22.7mV | 26.5mV | Pass |
| Cross-Load 1 | 8.2mV | 10.2mV | 16.0mV | 6.1mV | Pass |
| Cross-Load 2 | 10.9mV | 13.9mV | 20.4mV | 20.2mV | Pass |
Ripple suppression is great overall, with the +12V rail staying below 11mV at full load and not surpassing 12mV with 110% of the PSU's maximum-rated load.
With that said, we tested this PSU at 40°C and not the 45°C we usually use due to the problems faced with our first sample. Still, we're pretty sure that the 5°C difference won't affect this unit's ripple suppression in a meaningful way.
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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