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Load Regulation, Hold-Up Time & 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.
The hold-up time we measure is pretty long, and the 750 B3's power-good signal is accurate.
Inrush Current
For details on our inrush current testing, please click here.
The inrush current is at normal levels with 115V input, but it's quite high at 230V.
Load Regulation And Efficiency Measurements
The first set of tests reveals the stability of the voltage rails and the 750 B3'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 compatible with Intel's C6/C7 sleep states 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 | PSU Noise | Temps (In/Out) | PF/AC Volts |
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 4.385A | 1.984A | 1.984A | 0.985A | 74.767 | 78.388% | 0 RPM | <6.0 dB(A) | 42.57°C | 0.956 |
| 12.127V | 5.050V | 3.320V | 5.060V | 95.381 | 38.14°C | 115.19V | ||||
| 2 | 9.808A | 2.971A | 2.981A | 1.188A | 149.737 | 82.908% | 1180 RPM | 26.7 dB(A) | 40.01°C | 0.982 |
| 12.120V | 5.044V | 3.317V | 5.042V | 180.607 | 44.56°C | 115.19V | ||||
| 3 | 15.583A | 3.479A | 3.496A | 1.391A | 224.879 | 85.474% | 1218 RPM | 27.3 dB(A) | 40.19°C | 0.989 |
| 12.114V | 5.039V | 3.314V | 5.025V | 263.096 | 44.85°C | 115.20V | ||||
| 4 | 21.355A | 3.977A | 3.983A | 1.595A | 299.740 | 86.755% | 1240 RPM | 27.8 dB(A) | 40.40°C | 0.992 |
| 12.107V | 5.035V | 3.311V | 5.005V | 345.503 | 45.39°C | 115.19V | ||||
| 5 | 26.802A | 4.974A | 4.986A | 1.803A | 374.721 | 86.934% | 1315 RPM | 30.4 dB(A) | 40.85°C | 0.994 |
| 12.097V | 5.030V | 3.307V | 4.985V | 431.041 | 46.07°C | 115.19V | ||||
| 6 | 32.255A | 5.975A | 5.991A | 2.010A | 449.621 | 86.672% | 1425 RPM | 32.3 dB(A) | 41.39°C | 0.995 |
| 12.086V | 5.024V | 3.303V | 4.965V | 518.762 | 46.64°C | 115.19V | ||||
| 7 | 37.723A | 6.982A | 6.996A | 2.222A | 524.620 | 86.079% | 1518 RPM | 35.4 dB(A) | 42.14°C | 0.996 |
| 12.075V | 5.019V | 3.300V | 4.944V | 609.464 | 47.49°C | 115.22V | ||||
| 8 | 43.204A | 7.984A | 8.010A | 2.435A | 599.523 | 85.391% | 1645 RPM | 37.4 dB(A) | 42.86°C | 0.996 |
| 12.062V | 5.012V | 3.295V | 4.923V | 702.091 | 48.44°C | 115.19V | ||||
| 9 | 49.128A | 8.487A | 8.535A | 2.440A | 674.581 | 84.523% | 1796 RPM | 41.4 dB(A) | 44.65°C | 0.996 |
| 12.050V | 5.009V | 3.292V | 4.910V | 798.101 | 50.49°C | 115.19V | ||||
| 10 | 54.814A | 9.002A | 9.050A | 3.078A | 749.458 | 83.619% | 1910 RPM | 42.1 dB(A) | 45.68°C | 0.996 |
| 12.036V | 5.004V | 3.281V | 4.866V | 896.273 | 51.81°C | 115.19V | ||||
| 11 | 61.100A | 9.012A | 9.065A | 3.085A | 824.374 | 82.633% | 2014 RPM | 43.1 dB(A) | 47.08°C | 0.997 |
| 12.024V | 4.998V | 3.275V | 4.855V | 997.629 | 53.48°C | 115.18V | ||||
| CL1 | 0.098A | 14.027A | 14.003A | 0.004A | 117.483 | 75.801% | 1425 RPM | 32.3 dB(A) | 44.06°C | 0.977 |
| 12.119V | 5.027V | 3.268V | 5.087V | 154.989 | 49.72°C | 115.20V | ||||
| CL2 | 62.446A | 1.003A | 1.002A | 1.002A | 764.673 | 83.995% | 1945 RPM | 42.1 dB(A) | 46.78°C | 0.997 |
| 12.032V | 5.013V | 3.287V | 4.991V | 910.382 | 52.70°C | 115.19V |
Load regulation is fairly tight on all of the rails except for 5VSB, which is worth noting from a budget-oriented platform. Meanwhile, the 750 B3 delivers full power at very high ambient temperatures (>45°C) without breaking a sweat. Its output noise remains low until the 50% load test, after which it exceeds 30 dB(A) during the sixth test and more than 40 dB(A) from the ninth test and up. Generally, though, the fan profile isn't that aggressive, considering this is a relatively low-efficiency PSU.
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