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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.
Our measured hold-up time exceeds 20ms. Meanwhile, the power-good signal is accurate and >16ms, meaning it satisfies the corresponding ATX specification requirement.
Inrush Current
For details on our inrush current testing, please click here.
The inrush current with both voltage inputs is pretty low, given this PSU's high capacity.
Load Regulation And Efficiency Measurements
The first set of tests reveals the stability of the voltage rails and the EDT1250EWT'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 | 8.597A | 1.974A | 2.003A | 0.991A | 124.785 | 90.803% | 0 RPM | <6.0 dB(A) | 45.25°C | 0.983 |
| 12.004V | 5.062V | 3.293V | 5.043V | 137.424 | 38.07°C | 115.10V | ||||
| 2 | 18.235A | 2.959A | 3.006A | 1.190A | 249.621 | 93.105% | 0 RPM | <6.0 dB(A) | 45.76°C | 0.995 |
| 11.997V | 5.059V | 3.290V | 5.038V | 268.107 | 38.41°C | 115.10V | ||||
| 3 | 28.245A | 3.464A | 3.523A | 1.391A | 374.781 | 93.574% | 0 RPM | <6.0 dB(A) | 46.57°C | 0.997 |
| 11.991V | 5.056V | 3.287V | 5.033V | 400.518 | 38.77°C | 115.11V | ||||
| 4 | 38.241A | 3.953A | 4.017A | 1.591A | 499.522 | 93.450% | 0 RPM | <6.0 dB(A) | 47.45°C | 0.998 |
| 11.986V | 5.053V | 3.284V | 5.028V | 534.533 | 39.30°C | 115.10V | ||||
| 5 | 47.903A | 4.953A | 5.028A | 1.791A | 624.388 | 93.017% | 0 RPM | <6.0 dB(A) | 48.24°C | 0.999 |
| 11.980V | 5.052V | 3.280V | 5.022V | 671.263 | 39.75°C | 115.10V | ||||
| 6 | 57.570A | 5.943A | 6.038A | 1.990A | 749.301 | 92.394% | 505 RPM | 7.7 dB(A) | 41.67°C | 0.999 |
| 11.977V | 5.049V | 3.278V | 5.018V | 810.988 | 50.48°C | 115.12V | ||||
| 7 | 67.251A | 6.939A | 7.052A | 2.194A | 874.081 | 91.322% | 778 RPM | 17.7 dB(A) | 42.85°C | 0.999 |
| 11.970V | 5.045V | 3.274V | 5.010V | 957.138 | 52.11°C | 115.13V | ||||
| 8 | 76.937A | 7.930A | 8.070A | 2.396A | 999.077 | 90.402% | 979 RPM | 25.1 dB(A) | 44.37°C | 0.999 |
| 11.967V | 5.042V | 3.271V | 5.005V | 1105.151 | 54.38°C | 115.13V | ||||
| 9 | 87.096A | 8.443A | 8.596A | 2.395A | 1124.191 | 89.549% | 1144 RPM | 29.0 dB(A) | 45.19°C | 0.999 |
| 11.959V | 5.039V | 3.267V | 5.003V | 1255.396 | 55.53°C | 115.14V | ||||
| 10 | 97.008A | 8.940A | 9.096A | 3.006A | 1249.039 | 88.713% | 1357 RPM | 33.9 dB(A) | 46.71°C | 0.998 |
| 11.951V | 5.035V | 3.264V | 4.988V | 1407.947 | 57.34°C | 115.13V | ||||
| 11 | 107.506A | 8.946A | 9.103A | 3.005A | 1373.966 | 87.951% | 1411 RPM | 35.6 dB(A) | 47.71°C | 0.998 |
| 11.946V | 5.033V | 3.262V | 4.985V | 1562.199 | 58.45°C | 115.14V | ||||
| CL1 | 0.098A | 12.011A | 12.005A | 0.004A | 101.505 | 85.883% | 0 RPM | <6.0 dB(A) | 52.96°C | 0.977 |
| 12.006V | 5.061V | 3.292V | 5.087V | 118.190 | 46.72°C | 115.14V | ||||
| CL2 | 104.103A | 1.002A | 1.004A | 1.002A | 1258.954 | 89.096% | 1410 RPM | 35.6 dB(A) | 47.10°C | 0.998 |
| 11.965V | 5.039V | 3.270V | 5.019V | 1413.035 | 56.61°C | 115.13V |
Load regulation is tight on all of the rails, and this PSU doesn't have a problem operating under very high temperatures. Efficiency-wise, the 80 PLUS Titanium requirements are met with 10% and 20% loads. However, under 50% and full loads, the EDT1250EWT doesn't hit the necessary levels. Obviously, the high temperature we use for testing is responsible for this result, since 80 PLUS conducts its test in a cooler (and less realistic) environment.
When it comes to output noise, the EDT1250EWT is quiet even under extremely tough operating conditions. In the worst-case overload test (#11), our measurements don't exceed 40 dB(A), but rather remain closer to 35 dB(A). Obviously, the fan profile is very relaxed. Enermax's passive mode lasts a long time, too, since the fan only starts spinning during our seventh load test.
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