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Load Regulation, Hold-Up Time And Inrush Current And Protections
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.
The hold-up time we measured is significantly longer than is needs to be, and the power-good signal drops while the rails are still within spec. This result is good to see; too many competing power supplies fail the same metric. To make matters worse, some manufacturers try cheating. Once their power-good signal drops, the rails are already out of spec, unnecessarily applying higher stress to system components.
Inrush Current
For details on our inrush current testing, please click here.
The inrush current is within normal levels.
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 | 3.580A | 1.985A | 1.989A | 0.995A | 64.77 | 84.90% | 0 RPM | 0 dB(A) | 44.80 °C | 0.965 |
| 12.062V | 5.040V | 3.312V | 5.018V | 76.29 | 38.79 °C | 115.1V | ||||
| 2 | 8.207A | 2.969A | 2.988A | 1.197A | 129.73 | 89.03% | 0 RPM | 0 dB(A) | 48.92 °C | 0.986 |
| 12.048V | 5.038V | 3.311V | 5.012V | 145.71 | 40.07 °C | 115.1V | ||||
| 3 | 13.192A | 3.477A | 3.503A | 1.395A | 194.84 | 90.28% | 0 RPM | 0 dB(A) | 49.91 °C | 0.992 |
| 12.034V | 5.036V | 3.310V | 5.006V | 215.81 | 40.34 °C | 115.1V | ||||
| 4 | 18.188A | 3.975A | 3.988A | 1.598A | 259.79 | 90.72% | 0 RPM | 0 dB(A) | 52.21 °C | 0.994 |
| 12.019V | 5.033V | 3.308V | 5.000V | 286.38 | 40.90 °C | 115.2V | ||||
| 5 | 22.848A | 4.969A | 4.988A | 1.801A | 324.76 | 90.37% | 0 RPM | 0 dB(A) | 53.81 °C | 0.995 |
| 12.004V | 5.031V | 3.307V | 4.995V | 359.36 | 41.72 °C | 115.1V | ||||
| 6 | 27.525A | 5.966A | 5.989A | 2.001A | 389.71 | 89.77% | 620 RPM | 22.0 dB(A) | 43.10 °C | 0.996 |
| 11.987V | 5.027V | 3.305V | 4.989V | 434.13 | 53.87 °C | 115.1V | ||||
| 7 | 32.202A | 6.971A | 6.994A | 2.205A | 454.66 | 89.39% | 620 RPM | 22.0 dB(A) | 43.78 °C | 0.997 |
| 11.973V | 5.023V | 3.303V | 4.983V | 508.63 | 54.95 °C | 115.1V | ||||
| 8 | 36.900A | 7.969A | 7.998A | 2.410A | 519.61 | 88.86% | 710 RPM | 22.8 dB(A) | 44.13 °C | 0.997 |
| 11.957V | 5.020V | 3.300V | 4.977V | 584.77 | 55.54 °C | 115.2V | ||||
| 9 | 42.050A | 8.473A | 8.517A | 2.410A | 584.72 | 88.29% | 920 RPM | 27.9 dB(A) | 45.37 °C | 0.997 |
| 11.941V | 5.017V | 3.299V | 4.975V | 662.24 | 57.08 °C | 115.1V | ||||
| 10 | 46.940A | 8.978A | 9.005A | 3.022A | 649.47 | 87.54% | 1100 RPM | 33.3 dB(A) | 47.83 °C | 0.997 |
| 11.925V | 5.015V | 3.298V | 4.959V | 741.91 | 60.08 °C | 115.1V | ||||
| 11 | 52.461A | 8.981A | 9.009A | 3.025A | 714.52 | 86.72% | 1315 RPM | 38.3 dB(A) | 49.12 °C | 0.997 |
| 11.910V | 5.013V | 3.296V | 4.956V | 823.95 | 61.71 °C | 115.1V | ||||
| CL1 | 0.100A | 16.025A | 16.005A | 0.004A | 134.76 | 82.71% | 690 RPM | 22.5 dB(A) | 46.56 °C | 0.988 |
| 12.040V | 5.020V | 3.317V | 5.070V | 162.94 | 55.18 °C | 115.1V | ||||
| CL2 | 54.124A | 1.003A | 1.003A | 1.002A | 658.69 | 88.09% | 1100 RPM | 33.3 dB(A) | 47.54 °C | 0.997 |
| 11.923V | 5.027V | 3.299V | 5.005V | 747.73 | 59.37 °C | 115.1V |
Besides quiet operation, even under extremely tough conditions, the RM650x also features tight load regulation on all of its minor rails. Load regulation is merely satisfactory on the +12V rail though; we'd like to see within 1% deviation, especially since we measured an amazing 0.49% on EVGA's 650 P2. Price-wise, that's a direct opponent.
Even at high ambient temperatures, the RM650x satisfies the 80 PLUS Gold requirements. Corsair takes the specification seriously, and prefers to be conservative with its ratings. In our opinion, that shows a lot of respect for its customers.
The PSU's fan starts to spin during our 60% load test. It takes the full load test to get it above 1000 RPM. Even in a worst-case 110% load scenario, the fan doesn't exceed 40 dB(A). We should also mention that, despite our best efforts, we couldn't get the fan rotating at full speed. This is the same fan used in Corsair's RM1000x and it easily covers that model's needs. It should come as no surprise that a 650W power supply presents less of a challenge.
