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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.
Hold-Up Time
Our hold-up time tests are described in detail here.
The hold-up time we measured is lower than 17ms, and to our disappointment, the power-good signal is inaccurate. It drops when the rails are already out of spec.
Inrush Current
For details on our inrush current testing, please click here.
The inrush current results are a little higher than the competition in this category.
Load Regulation And Efficiency Measurements
The first set of tests reveals the stability of the voltage rails and the Tokamak 1500'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 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 | 10.571A | 1.980A | 1.959A | 0.995A | 149.83 | 91.90% | 850 RPM | 33.1 dB(A) | 36.30°C | 0.939 |
| 12.131V | 5.049V | 3.367V | 5.023V | 163.03 | 39.49°C | 115.0V | ||||
| 2 | 22.195A | 2.967A | 2.939A | 1.195A | 299.77 | 93.85% | 850 RPM | 33.1 dB(A) | 37.31°C | 0.965 |
| 12.116V | 5.047V | 3.364V | 5.018V | 319.43 | 41.18°C | 115.0V | ||||
| 3 | 34.188A | 3.468A | 3.449A | 1.394A | 449.77 | 93.99% | 890 RPM | 35.1 dB(A) | 37.87°C | 0.978 |
| 12.101V | 5.043V | 3.361V | 5.010V | 478.54 | 42.98°C | 115.0V | ||||
| 4 | 46.205A | 3.962A | 3.928A | 1.596A | 599.58 | 93.65% | 1430 RPM | 46.3 dB(A) | 38.97°C | 0.984 |
| 12.086V | 5.040V | 3.359V | 5.003V | 640.26 | 44.26°C | 115.0V | ||||
| 5 | 57.923A | 4.966A | 4.915A | 1.801A | 749.64 | 92.97% | 1785 RPM | 51.5 dB(A) | 39.44°C | 0.987 |
| 12.070V | 5.037V | 3.356V | 4.998V | 806.29 | 44.97°C | 115.0V | ||||
| 6 | 69.651A | 5.953A | 5.901A | 2.000A | 899.39 | 91.80% | 2220 RPM | 56.1 dB(A) | 40.66°C | 0.990 |
| 12.055V | 5.034V | 3.354V | 4.993V | 979.75 | 46.56°C | 115.0V | ||||
| 7 | 81.419A | 6.955A | 6.888A | 2.202A | 1049.36 | 91.20% | 2420 RPM | 58.2 dB(A) | 42.90°C | 0.992 |
| 12.040V | 5.032V | 3.353V | 4.988V | 1150.65 | 49.22°C | 115.0V | ||||
| 8 | 93.245A | 7.951A | 7.878A | 2.407A | 1199.27 | 90.59% | 2450 RPM | 58.6 dB(A) | 43.16°C | 0.993 |
| 12.021V | 5.028V | 3.351V | 4.983V | 1323.86 | 49.94°C | 115.1V | ||||
| 9 | 105.527A | 8.459A | 8.391A | 2.404A | 1349.33 | 89.98% | 2450 RPM | 58.6 dB(A) | 43.82°C | 0.994 |
| 12.004V | 5.026V | 3.348V | 4.983V | 1499.62 | 51.65°C | 115.1V | ||||
| 10 | 117.603A | 8.961A | 8.881A | 3.021A | 1499.28 | 89.19% | 2450 RPM | 58.6 dB(A) | 44.46°C | 0.994 |
| 11.986V | 5.022V | 3.344V | 4.962V | 1681.00 | 53.36°C | 115.1V | ||||
| 11 | 130.298A | 8.965A | 8.890A | 3.020A | 1649.34 | 88.50% | 2450 RPM | 58.6 dB(A) | 44.81°C | 0.994 |
| 11.970V | 5.020V | 3.340V | 4.959V | 1863.57 | 54.11°C | 115.1V | ||||
| CL1 | 0.103A | 14.020A | 14.005A | 0.004A | 119.30 | 82.99% | 2390 RPM | 57.5 dB(A) | 43.15°C | 0.935 |
| 12.125V | 5.042V | 3.380V | 5.097V | 143.75 | 49.09°C | 115.0V | ||||
| CL2 | 124.928A | 1.000A | 1.003A | 0.004A | 1506.53 | 89.49% | 2450 RPM | 58.6 dB(A) | 44.46°C | 0.995 |
| 11.992V | 5.029V | 3.338V | 5.038V | 1683.45 | 53.22°C | 115.1V |
Load regulation is tight, especially on the minor rails. In addition, the Tokamak has no problem delivering more than its full power under high operating temperatures. The only issue we see so far is the fan's loud noise under loads in excess of 600W. The minimum fan speed could also be lower.
With 10% and 20% of its maximum-rated loads, this PSU easily meets the 80 PLUS Titanium requirements. However, in the middle range it falls 1% short of the specification's target. In addition, it's not able to hit 90% under a full load. As we're always forced to mention, the 80 PLUS organization doesn't test under real-world conditions inside of a case. It instead chooses to measure at 23°C +/-5°C ambient.
