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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 PSUs.
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 was very low, but at least the power-good signal was accurate. CWT's design performed better, despite its lower-capacity bulk cap. However, it still fell short of the 17 millisecond (ms) hold-up time that the ATX spec requires.
Inrush Current
For details on our inrush current testing, please click here.
We measured high inrush currents from Great Wall's platform with 230V input, while CWT's fared notably better with both voltage inputs.
Load Regulation & Efficiency Measurements
The first set of tests revealed the stability of the voltage rails and the CX450’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.
Corsair CX450 - CWT
| Test # | 12V | 5V | 3.3V | 5VSB | DC/AC (Watts) | Efficiency | Fan Speed | PSU Noise | Temps (In/Out) | PF/AC Volts |
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 1.925A | 1.974A | 1.998A | 0.986A | 44.755 | 76.962% | 818 RPM | 13.8 dB(A) | 37.88°C | 0.977 |
| 12.056V | 5.053V | 3.296V | 5.058V | 58.152 | 44.53°C | 115.12V | ||||
| 2 | 4.888A | 2.962A | 3.002A | 1.186A | 89.727 | 83.357% | 818 RPM | 13.8 dB(A) | 38.08°C | 0.991 |
| 12.047V | 5.052V | 3.294V | 5.049V | 107.642 | 45.12°C | 115.12V | ||||
| 3 | 8.208A | 3.467A | 3.519A | 1.386A | 134.899 | 85.645% | 818 RPM | 13.8 dB(A) | 38.55°C | 0.995 |
| 12.039V | 5.050V | 3.293V | 5.041V | 157.510 | 46.96°C | 115.12V | ||||
| 4 | 11.520A | 3.961A | 4.006A | 1.585A | 179.790 | 86.487% | 818 RPM | 13.8 dB(A) | 39.06°C | 0.996 |
| 12.033V | 5.049V | 3.293V | 5.034V | 207.881 | 48.52°C | 115.12V | ||||
| 5 | 14.490A | 4.960A | 5.010A | 1.791A | 224.794 | 86.423% | 1015 RPM | 21.1 dB(A) | 39.74°C | 0.997 |
| 12.027V | 5.048V | 3.290V | 5.026V | 260.110 | 49.64°C | 115.12V | ||||
| 6 | 17.481A | 5.946A | 6.017A | 1.991A | 269.741 | 86.157% | 1286 RPM | 28.5 dB(A) | 40.52°C | 0.998 |
| 12.011V | 5.045V | 3.289V | 5.017V | 313.081 | 50.58°C | 115.12V | ||||
| 7 | 20.458A | 6.944A | 7.022A | 2.196A | 314.715 | 85.560% | 1578 RPM | 34.1 dB(A) | 41.67°C | 0.998 |
| 12.006V | 5.043V | 3.287V | 5.007V | 367.830 | 52.20°C | 115.12V | ||||
| 8 | 23.440A | 7.935A | 8.034A | 2.400A | 359.676 | 84.894% | 1630 RPM | 35.1 dB(A) | 42.14°C | 0.998 |
| 12.000V | 5.042V | 3.285V | 4.998V | 423.679 | 53.14°C | 115.12V | ||||
| 9 | 26.871A | 8.439A | 8.553A | 2.401A | 404.800 | 84.164% | 1630 RPM | 35.1 dB(A) | 44.01°C | 0.998 |
| 11.990V | 5.041V | 3.284V | 4.993V | 480.965 | 56.41°C | 115.12V | ||||
| 10 | 30.031A | 8.936A | 9.042A | 3.011A | 449.570 | 83.142% | 1630 RPM | 35.1 dB(A) | 45.34°C | 0.998 |
| 11.983V | 5.039V | 3.284V | 4.977V | 540.723 | 60.06°C | 115.12V | ||||
| 11 | 33.815A | 8.934A | 9.044A | 3.015A | 494.534 | 82.117% | 1630 RPM | 35.1 dB(A) | 46.52°C | 0.998 |
| 11.972V | 5.039V | 3.283V | 4.972V | 602.234 | 64.16°C | 115.12V | ||||
| CL1 | 0.100A | 13.019A | 13.004A | 0.005A | 109.758 | 80.682% | 1381 RPM | 30.8 dB(A) | 44.16°C | 0.993 |
| 12.046V | 5.049V | 3.291V | 5.047V | 136.038 | 53.00°C | 115.13V | ||||
| CL2 | 37.478A | 1.004A | 1.003A | 1.002A | 462.348 | 83.718% | 1630 RPM | 35.1 dB(A) | 44.95°C | 0.998 |
| 11.979V | 5.046V | 3.289V | 5.024V | 552.268 | 59.21°C | 115.12V |
Corsair CX450 - Great Wall
| Test # | 12V | 5V | 3.3V | 5VSB | DC/AC (Watts) | Efficiency | Fan Speed | PSU Noise | Temps (In/Out) | PF/AC Volts |
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 1.924A | 1.995A | 1.982A | 0.996A | 44.813 | 80.582% | 1230 RPM | 27.6 dB(A) | 40.07°C | 0.955 |
| 12.070V | 5.008V | 3.328V | 5.023V | 55.612 | 45.61°C | 115.31V | ||||
| 2 | 4.841A | 2.998A | 2.976A | 1.197A | 89.319 | 85.465% | 1340 RPM | 29.3 dB(A) | 40.76°C | 0.981 |
| 12.066V | 5.006V | 3.326V | 5.014V | 104.509 | 46.71°C | 115.25V | ||||
| 3 | 8.162A | 3.498A | 3.457A | 1.398A | 134.428 | 87.103% | 1395 RPM | 31.5 dB(A) | 41.09°C | 0.988 |
| 12.060V | 5.004V | 3.324V | 5.007V | 154.333 | 48.21°C | 115.19V | ||||
| 4 | 11.484A | 3.997A | 3.973A | 1.601A | 179.644 | 87.516% | 1575 RPM | 35.1 dB(A) | 41.74°C | 0.990 |
| 12.056V | 5.003V | 3.321V | 4.998V | 205.269 | 50.76°C | 115.13V | ||||
| 5 | 14.475A | 5.000A | 4.971A | 1.804A | 224.927 | 87.265% | 1710 RPM | 37.7 dB(A) | 42.12°C | 0.992 |
| 12.050V | 5.001V | 3.319V | 4.989V | 257.751 | 51.89°C | 115.07V | ||||
| 6 | 17.403A | 6.003A | 5.966A | 2.008A | 269.436 | 86.899% | 1865 RPM | 40.2 dB(A) | 42.81°C | 0.993 |
| 12.046V | 4.999V | 3.317V | 4.981V | 310.057 | 53.15°C | 115.10V | ||||
| 7 | 20.396A | 7.006A | 6.967A | 2.213A | 314.729 | 86.036% | 1865 RPM | 40.2 dB(A) | 43.11°C | 0.994 |
| 12.042V | 4.998V | 3.316V | 4.971V | 365.809 | 54.46°C | 115.03V | ||||
| 8 | 23.392A | 8.007A | 7.966A | 2.419A | 360.029 | 85.148% | 1865 RPM | 40.2 dB(A) | 43.83°C | 0.995 |
| 12.039V | 4.997V | 3.314V | 4.962V | 422.828 | 55.64°C | 114.97V | ||||
| 9 | 26.793A | 8.508A | 8.456A | 2.421A | 404.935 | 83.918% | 1870 RPM | 40.3 dB(A) | 44.22°C | 0.995 |
| 12.034V | 4.995V | 3.312V | 4.958V | 482.539 | 56.86°C | 114.89V | ||||
| 10 | 29.931A | 9.014A | 8.975A | 3.038A | 449.755 | 82.743% | 1865 RPM | 40.2 dB(A) | 45.32°C | 0.994 |
| 12.029V | 4.993V | 3.310V | 4.938V | 543.555 | 58.66°C | 114.87V | ||||
| 11 | 33.661A | 9.014A | 8.974A | 3.042A | 494.583 | 81.830% | 1865 RPM | 40.2 dB(A) | 46.51°C | 0.994 |
| 12.028V | 4.993V | 3.309V | 4.933V | 604.405 | 60.88°C | 114.85V | ||||
| CL1 | 0.136A | 13.001A | 12.999A | 0.000A | 109.905 | 81.270% | 1862 RPM | 40.1 dB(A) | 43.10°C | 0.987 |
| 12.056V | 5.004V | 3.324V | 5.029V | 135.234 | 54.76°C | 115.21V | ||||
| CL2 | 37.419A | 1.003A | 1.001A | 1.000A | 463.776 | 83.467% | 1873 RPM | 40.3 dB(A) | 45.55°C | 0.995 |
| 12.038V | 4.999V | 3.314V | 4.994V | 555.639 | 59.00°C | 114.91V |
Both PSUs demonstrated good load regulation. However, Great Wall's version won in this particular comparison. Its fan spun aggressively once the operating temperatures started climbing. But we expected that from a lower-efficiency power supply. On the other hand, though, CWT's fan profile was more relaxed under the same operating conditions.
The two CX450s delivered their full power without any problems at ambient temperatures greater than 46°C (113°F) . And both easily met 80 PLUS requirements for Bronze certification, even under our tough operating conditions.
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