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Ripple Measurements
To learn how we measure ripple, please click here.
The following table includes the ripple levels we measured on the PSU’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 | 5.9mV | 11.2mV | 11.4mV | 7.7mV | Pass |
| 20% Load | 5.1mV | 11.6mV | 11.6mV | 9.0mV | Pass |
| 30% Load | 6.2mV | 12.4mV | 12.4mV | 8.4mV | Pass |
| 40% Load | 7.3mV | 13.2mV | 12.4mV | 9.1mV | Pass |
| 50% Load | 8.6mV | 14.3mV | 13.7mV | 9.1mV | Pass |
| 60% Load | 11.0mV | 15.1mV | 14.6mV | 8.3mV | Pass |
| 70% Load | 13.6mV | 16.4mV | 16.2mV | 9.3mV | Pass |
| 80% Load | 16.2mV | 17.6mV | 18.1mV | 9.9mV | Pass |
| 90% Load | 19.1mV | 18.7mV | 18.6mV | 10.5mV | Pass |
| 100% Load | 23.1mV | 20.2mV | 20.0mV | 11.0mV | Pass |
| 110% Load | 27.1mV | 21.6mV | 19.8mV | 10.8mV | Pass |
| Cross-Load 1 | 16.2mV | 17.8mV | 25.1mV | 13.4mV | Pass |
| Cross-Load 2 | 24.4mV | 18.6mV | 13.3mV | 9.3mV | Pass |
Right out of the box, we observed excellent ripple suppression. However, there's no way to know how long the 450 BT can maintain that performance, since its secondary side is populated with low-quality filtering caps. Those will age much faster than the Japanese caps found in EVGA's more expensive PSUs.
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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