Load Regulation, Hold-Up Time, And Inrush Current
To learn more about our PSU tests and methodology, please check out How We Test Power Supply Units.
Bitfenix BWG550M
EVGA SuperNOVA 550 GS
EVGA SuperNOVA 550 G2
Primary Rails And 5VSB Load Regulation
Load Regulation testing is detailed here.
Hold-Up Time
Our hold-up time tests are described in detail here.
As expected, the hold-up time we measured is lower than 17ms. Thankfully the power-good signal is accurate, and it doesn't last longer than the unit's actual hold-up time.
The difference between the hold-up time and the moment the power-good signal is deasserted should be at least 1ms. As you can see, in this case it's only 0.62ms.
Inrush Current
For details on our inrush current testing, please click here.
The inrush current with both 115V and 230V is a little higher than the average in this wattage category. An NTC thermistor with increased resistance should be used instead of the only that's installed.
Load Regulation And Efficiency Measurements
The first set of tests reveals the stability of the voltage rails and the PSU's efficiency. The applied load equals (approximately) 10 to 110 percent of the maximum load the supply can handle, in increments of 10 percentage points.
We conducted two additional tests. During the first, we stressed the two minor rails (5V and 3.3V) with a high load, while the load at +12V was only 0.1A. This test reveals whether a PSU is Haswell-ready or not. In the second test, we determined the maximum load the +12V rail could handle with minimal load on the minor rails.
| Test # | 12V | 5V | 3.3V | 5VSB | DC/AC (Watts) | Efficiency | Fan Speed | Fan Noise | Temps (In/Out) | PF/AC Volts |
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 2.753A | 1.973A | 1.975A | 0.985A | 54.75 | 85.96% | 400 RPM | 21.3 dB(A) | 38.16°C | 0.944 |
| 12.054V | 5.058V | 3.338V | 5.070V | 63.69 | 40.99°C | 115.1V | ||||
| 2 | 6.552A | 2.960A | 2.967A | 1.182A | 109.74 | 89.76% | 400 RPM | 21.3 dB(A) | 39.16°C | 0.974 |
| 12.043V | 5.052V | 3.334V | 5.064V | 122.26 | 42.58°C | 115.1V | ||||
| 3 | 10.702A | 3.465A | 3.482A | 1.380A | 164.83 | 90.90% | 400 RPM | 21.3 dB(A) | 40.14°C | 0.982 |
| 12.032V | 5.047V | 3.329V | 5.059V | 181.34 | 44.13°C | 115.1V | ||||
| 4 | 14.857A | 3.962A | 3.968A | 1.580A | 219.76 | 91.22% | 400 RPM | 21.3 dB(A) | 41.00°C | 0.985 |
| 12.022V | 5.042V | 3.323V | 5.054V | 240.92 | 45.84°C | 115.1V | ||||
| 5 | 18.670A | 4.967A | 4.969A | 1.781A | 274.74 | 91.00% | 400 RPM | 21.3 dB(A) | 41.60°C | 0.986 |
| 12.011V | 5.036V | 3.319V | 5.047V | 301.91 | 47.51°C | 115.1V | ||||
| 6 | 22.493A | 5.961A | 5.972A | 1.980A | 329.68 | 90.18% | 400 RPM | 21.3 dB(A) | 42.91°C | 0.987 |
| 12.000V | 5.031V | 3.314V | 5.040V | 365.59 | 50.75°C | 115.1V | ||||
| 7 | 26.322A | 6.968A | 6.979A | 2.182A | 384.67 | 89.64% | 650 RPM | 26.5 dB(A) | 43.19°C | 0.986 |
| 11.989V | 5.025V | 3.309V | 5.034V | 429.15 | 51.41°C | 115.1V | ||||
| 8 | 30.161A | 7.969A | 7.990A | 2.385A | 439.62 | 89.04% | 830 RPM | 31.6 dB(A) | 44.10°C | 0.985 |
| 11.977V | 5.019V | 3.303V | 5.027V | 493.75 | 52.97°C | 115.1V | ||||
| 9 | 34.439A | 8.476A | 8.518A | 2.385A | 494.69 | 88.45% | 1260 RPM | 41.0 dB(A) | 45.28°C | 0.986 |
| 11.966V | 5.015V | 3.299V | 5.025V | 559.29 | 54.80°C | 115.1V | ||||
| 10 | 38.676A | 8.987A | 9.016A | 2.488A | 549.54 | 87.90% | 1400 RPM | 42.7 dB(A) | 45.94°C | 0.987 |
| 11.954V | 5.009V | 3.294V | 5.020V | 625.18 | 53.35°C | 115.1V | ||||
| 11 | 43.323A | 8.996A | 9.022A | 2.489A | 604.57 | 87.00% | 1400 RPM | 42.7 dB(A) | 45.99°C | 0.988 |
| 11.942V | 5.005V | 3.291V | 5.018V | 694.89 | 54.19°C | 115.1V | ||||
| CL1 | 0.100A | 12.010A | 12.005A | 0.003A | 101.51 | 84.47% | 400 RPM | 21.3 dB(A) | 43.07°C | 0.974 |
| 12.037V | 5.033V | 3.319V | 5.090V | 120.18 | 52.80°C | 115.1V | ||||
| CL2 | 45.784A | 1.002A | 1.003A | 1.002A | 560.96 | 88.35% | 1400 RPM | 42.7 dB(A) | 44.47°C | 0.987 |
| 11.959V | 5.029V | 3.312V | 5.058V | 634.91 | 51.75°C | 115.1V |
Load regulation is fairly tight on all rails, and the PSU easily meets the 80 PLUS Gold requirements, even under high ambient temperatures.
Output noise remains low thanks to a conservative fan profile and low-speed fan. We have to push the PSU hard in order to make the fan spin higher than 1000 RPM. The transition to higher speeds could be smoother, since the difference between the 80% and 90% load tests is huge.
In any case, the PSU performs well. It doesn't seem to have any problem running in unforgiving environments as it delivers full load for prolonged periods.