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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.
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.
Though the measured hold-up time exceeds 17ms, the power-good hold-up time is lower than 16ms. By tuning this delay, the power-good signal could be made to exceed 16ms. At least this signal is accurate, since it drops before the rails go out of spec.
Inrush Current
For details on our inrush current testing, please click here.
Inrush current is high with both voltage inputs. HEC should take a closer look at this.
Load Regulation And Efficiency Measurements
The first set of tests reveals the stability of the voltage rails and the EVGA 850 BQ's efficiency. The applied load equals (approximately) 10 to 110 percent of the PSU's maximum load 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 | 5.165A | 1.964A | 1.936A | 0.995A | 84.79 | 80.93% | 1120 RPM | 38.8 dB(A) | 37.00°C | 0.987 |
| 12.235V | 5.093V | 3.405V | 5.023V | 104.77 | 40.40°C | 115.2V | ||||
| 2 | 11.365A | 2.948A | 2.919A | 1.196A | 169.60 | 85.22% | 1120 RPM | 38.8 dB(A) | 38.47°C | 0.983 |
| 12.210V | 5.074V | 3.388V | 5.003V | 199.01 | 42.94°C | 115.1V | ||||
| 3 | 17.964A | 3.458A | 3.434A | 1.400A | 254.85 | 86.60% | 1135 RPM | 39.0 dB(A) | 40.11°C | 0.990 |
| 12.179V | 5.059V | 3.375V | 4.985V | 294.28 | 46.06°C | 115.1V | ||||
| 4 | 24.564A | 3.963A | 3.924A | 1.609A | 339.73 | 86.80% | 1150 RPM | 39.2 dB(A) | 41.98°C | 0.993 |
| 12.154V | 5.045V | 3.362V | 4.968V | 391.38 | 48.83°C | 115.1V | ||||
| 5 | 30.866A | 4.972A | 4.930A | 1.816A | 424.68 | 86.43% | 1395 RPM | 43.0 dB(A) | 43.48°C | 0.995 |
| 12.124V | 5.025V | 3.345V | 4.949V | 491.38 | 50.53°C | 115.1V | ||||
| 6 | 37.190A | 5.994A | 5.945A | 2.025A | 509.67 | 85.74% | 1550 RPM | 46.1 dB(A) | 43.64°C | 0.996 |
| 12.097V | 5.005V | 3.330V | 4.932V | 594.47 | 51.50°C | 115.1V | ||||
| 7 | 43.542A | 7.019A | 6.973A | 2.239A | 594.62 | 85.00% | 1665 RPM | 48.3 dB(A) | 43.84°C | 0.997 |
| 12.070V | 4.984V | 3.312V | 4.910V | 699.59 | 52.16°C | 115.1V | ||||
| 8 | 49.917A | 8.061A | 8.013A | 2.451A | 679.49 | 84.12% | 1780 RPM | 49.0 dB(A) | 44.48°C | 0.998 |
| 12.042V | 4.963V | 3.294V | 4.890V | 807.76 | 53.13°C | 115.1V | ||||
| 9 | 56.777A | 8.594A | 8.566A | 2.459A | 764.49 | 83.14% | 1830 RPM | 49.7 dB(A) | 45.29°C | 0.998 |
| 12.010V | 4.946V | 3.280V | 4.877V | 919.49 | 54.20°C | 115.1V | ||||
| 10 | 63.378A | 9.127A | 9.090A | 3.091A | 849.33 | 82.22% | 1840 RPM | 50.0 dB(A) | 45.46°C | 0.998 |
| 11.986V | 4.930V | 3.267V | 4.849V | 1033.00 | 55.15°C | 115.2V | ||||
| 11 | 70.652A | 9.152A | 9.126A | 3.099A | 934.26 | 81.08% | 1925 RPM | 51.2 dB(A) | 46.32°C | 0.998 |
| 11.954V | 4.918V | 3.253V | 4.837V | 1152.23 | 56.17°C | 115.1V | ||||
| CL1 | 0.101A | 19.021A | 19.001A | 0.003A | 156.96 | 77.77% | 1330 RPM | 42.2 dB(A) | 44.07°C | 0.984 |
| 12.184V | 4.931V | 3.259V | 4.976V | 201.83 | 53.34°C | 115.1V | ||||
| CL2 | 69.958A | 1.002A | 1.003A | 1.002A | 851.51 | 82.77% | 1885 RPM | 50.9 dB(A) | 46.58°C | 0.998 |
| 11.982V | 5.003V | 3.317V | 4.922V | 1028.80 | 56.43°C | 115.1V |
Load regulation is bad, especially on the minor rails (including 5VSB). At least our efficiency measurements do satisfy the 80 PLUS Bronze requirements. Also, the PSU doesn't have a problem delivering its full power under a very high ambient temperature, which actually exceeds EVGA's official maximum rating (40°C). The fan is super noisy though, and even under lighter loads it spins fast. Obviously HEC wants to cool the secondary side's Teapo SC capacitors as effectively as possible, so it tuned the fan's minimum speed to 1120 RPM.
