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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.
The following charts show the voltage values of the main rails, recorded over a range from 40W to the maximum specified load, and the deviation (in percentage) for the same load range. You will also find a chart showing how the 5VSB rail deals with the load we throw at it.
Hold-Up Time
Our hold-up time tests are described in detail here.
The hold-up time was only 0.2ms away from our desired measurement. We are going to give it a pass, since we always use the least-attractive hold-up test reading (and we repeat them many times) as a worst-case scenario.
Inrush Current
For details on our inrush current testing, please click here.
The registered inrush current was low with 115V input and at normal levels with 230V.
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 percent 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 0.10A. This test reveals whether a PSU is Haswell-ready. In the second test, we determined the maximum load the +12V rail could handle while the load on the minor rails was minimal.
| Test | 12V | 5V | 3.3V | 5VSB | PowerDC/AC(W) | Efficiency(%) | FanSpeed(RPM) | FanNoisedB(A) | TempIn/Out(°C) | PF/AC(V) |
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 5.218A | 1.973A | 1.984A | 0.980A | 84.78 | 85.08 | 470 | 19.7 | 38.57 | 0.976 |
| 12.110V | 5.073V | 3.321V | 5.095V | 99.65 | 40.75 | 115 | ||||
| 2 | 11.466A | 2.957A | 2.985A | 1.179A | 169.62 | 89.62 | 560 | 21.3 | 39.29 | 0.994 |
| 12.102V | 5.065V | 3.313V | 5.084V | 189.27 | 42.08 | 115 | ||||
| 3 | 18.089A | 3.457A | 3.504A | 1.377A | 254.81 | 90.98 | 710 | 25.2 | 39.53 | 0.995 |
| 12.093V | 5.059V | 3.307V | 5.071V | 280.06 | 42.55 | 115 | ||||
| 4 | 24.699A | 3.95A | 3.998A | 1.579A | 339.66 | 91.63 | 820 | 30.1 | 39.84 | 0.997 |
| 12.086V | 5.053V | 3.300V | 5.062V | 370.70 | 43.07 | 115 | ||||
| 5 | 30.975A | 4.956A | 5.009A | 1.780A | 424.60 | 91.72 | 1010 | 39.2 | 40.58 | 0.997 |
| 12.078V | 5.045V | 3.293V | 5.049V | 462.92 | 44.03 | 115 | ||||
| 6 | 37.270A | 5.952A | 6.026A | 1.983A | 509.60 | 91.55 | 1235 | 40.3 | 41.65 | 0.998 |
| 12.070V | 5.035V | 3.285V | 5.037V | 556.64 | 45.57 | 115 | ||||
| 7 | 43.570A | 6.965A | 7.049A | 2.186A | 594.59 | 91.23 | 1420 | 42.4 | 42.24 | 0.998 |
| 12.061V | 5.027V | 3.276V | 5.025V | 651.78 | 46.44 | 114.9 | ||||
| 8 | 49.871A | 7.969A | 8.073A | 2.392A | 679.45 | 90.81 | 1480 | 42.7 | 43.03 | 0.998 |
| 12.053V | 5.018V | 3.268V | 5.010V | 748.20 | 47.71 | 114.9 | ||||
| 9 | 56.614A | 8.478A | 8.612A | 2.395A | 764.55 | 90.37 | 1480 | 42.7 | 43.98 | 0.998 |
| 12.046V | 5.012V | 3.263V | 5.005V | 846.05 | 49.27 | 114.9 | ||||
| 10 | 63.107A | 8.995A | 9.121A | 3.010A | 849.38 | 89.76 | 1480 | 42.7 | 44.82 | 0.999 |
| 12.038V | 5.004V | 3.256V | 4.979V | 946.25 | 50.65 | 114.9 | ||||
| 11 | 70.198A | 9.006A | 9.129A | 3.013A | 934.33 | 89.16 | 1480 | 42.7 | 46.22 | 0.999 |
| 12.032V | 4.999V | 3.253V | 4.975V | 1047.90 | 52.39 | 114.9 | ||||
| CL1 | 0.099A | 17.015A | 17.004A | 0.001A | 141.66 | 84.46 | 1480 | 42.7 | 44.11 | 0.993 |
| 12.107V | 4.995V | 3.262V | 5.112V | 167.73 | 48.8 | 115 | ||||
| CL2 | 69.954A | 1.002A | 1.003A | 1.001A | 855.66 | 90.15 | 1480 | 42.7 | 45.35 | 0.999 |
| 12.040V | 5.036V | 3.290V | 5.063V | 949.20 | 51.22 | 114.9 |
Load regulation was top notch at +12V, and on the other three rails it was also pretty good. In addition, the Dark Power PSU was very close to the official 80 PLUS Platinum efficiency requirements, which are rated at much lower operating temperatures than our hotbox's. The noise output up to the 40-percent load test was low, increasing significantly from the 50-percent load test and above. However, even in the worst-case scenario, with the fan spinning at full speed, the noise didn't exceed 43 dB(A). Other PSUs in similar conditions easily surpass 50 dB(A). Finally, the unit easily delivered its full power at high ambient temperatures, proving that its platform is tolerant of extreme heat conditions.
