bequiet! Straight Power E9 CM 680 W Power Supply Review
Ripple and Noise Tests
Contents
Voltages at the power supply outputs must be as “clean” as possible, with no noise or oscillation (also known as “ripple”). The maximum ripple and noise levels allowed are 120 mV for +12 V and -12 V outputs, and 50 mV for +5 V, +3.3 V and +5VSB outputs. All values are peak-to-peak figures. We consider a power supply as being top-notch if it can produce half or less of the maximum allowed ripple and noise levels.
The bequiet! Straight Power E9 CM 680 W provided ripple and noise levels within the proper range, although they were too high during test five for us to consider this unit “flawless.”
| Input | Test 1 | Test 2 | Test 3 | Test 4 | Test 5 |
| +12VA | 25.6 mV | 28.2 mV | 36.8 mV | 51.4 mV | 78.4 mV |
| +12VB | 30.4 mV | 33.8 mV | 43.2 mV | 57.6 mV | 85.6 mV |
| +5 V | 14.2 mV | 15.4 mV | 18.6 mV | 2 3.0 mV |
40.2 mV |
| +3.3 V | 21.4 mV | 24.4 mV | 27.2 mV | 29.4 mV | 31.4 mV |
| +5VSB | 12.4 mV | 7.8 mV | 8.2 mV | 10.4 mV | 10.4 mV |
| -12 V | 53.2 mV | 59.4 mV | 64.4 mV | 71.2 mV | 91.6 mV |
Below you can see the waveforms of the outputs during test five.
Figure 19: +12VA input from load tester during test five at 678.4 W (78.4 mV)
Figure 20: +12VB input from load tester during test five at 678.4 W (85.6 mV)
Figure 21: +5V rail during test five at 678.4 W (40.2 mV)
Figure 22: +3.3 V rail during test five at 678.4 W (31.4 mV)
Let’s see if we can pull more than 680 W from this unit.