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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.
It is nice to see an SFX-based power supply demonstrating an almost-20ms hold-up time, and with an accurate power-good signal.
Inrush Current
For details on our inrush current testing, please click here.
Measured inrush current is normal for a 500W PSU.
Load Regulation And Efficiency Measurements
The first set of tests reveals the stability of the voltage rails and the SX500-G'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 | 2.305A | 1.965A | 1.970A | 0.986A | 49.780 | 79.716% | 898 RPM | 13.2 dB(A) | 38.04°C | 0.961 |
| 12.228V | 5.098V | 3.344V | 5.060V | 62.447 | 48.55°C | 115.18V | ||||
| 2 | 5.642A | 2.941A | 2.962A | 1.186A | 99.754 | 86.861% | 898 RPM | 13.2 dB(A) | 38.42°C | 0.983 |
| 12.213V | 5.092V | 3.338V | 5.047V | 114.843 | 51.11°C | 115.18V | ||||
| 3 | 9.321A | 3.443A | 3.478A | 1.387A | 149.888 | 89.825% | 898 RPM | 13.2 dB(A) | 38.85°C | 0.987 |
| 12.209V | 5.087V | 3.332V | 5.036V | 166.867 | 53.92°C | 115.18V | ||||
| 4 | 13.002A | 3.934A | 3.967A | 1.591A | 199.769 | 90.385% | 898 RPM | 13.2 dB(A) | 39.15°C | 0.989 |
| 12.197V | 5.081V | 3.326V | 5.028V | 221.020 | 57.92°C | 115.17V | ||||
| 5 | 16.353A | 4.929A | 4.968A | 1.794A | 249.791 | 90.392% | 898 RPM | 13.2 dB(A) | 40.14°C | 0.993 |
| 12.187V | 5.075V | 3.319V | 5.013V | 276.343 | 62.69°C | 115.17V | ||||
| 6 | 19.707A | 5.914A | 5.977A | 2.001A | 299.727 | 90.047% | 1405 RPM | 22.9 dB(A) | 40.51°C | 0.995 |
| 12.176V | 5.069V | 3.312V | 4.998V | 332.857 | 64.10°C | 115.17V | ||||
| 7 | 23.074A | 6.918A | 6.988A | 2.204A | 349.766 | 89.690% | 1575 RPM | 25.3 dB(A) | 41.24°C | 0.996 |
| 12.163V | 5.064V | 3.305V | 4.986V | 389.971 | 66.10°C | 115.17V | ||||
| 8 | 26.446A | 7.906A | 8.006A | 2.410A | 399.717 | 89.183% | 2048 RPM | 33.6 dB(A) | 42.34°C | 0.996 |
| 12.151V | 5.058V | 3.296V | 4.977V | 448.198 | 66.99°C | 115.17V | ||||
| 9 | 30.242A | 8.413A | 8.533A | 2.411A | 449.745 | 88.733% | 2048 RPM | 33.6 dB(A) | 43.17°C | 0.997 |
| 12.140V | 5.054V | 3.293V | 4.972V | 506.851 | 70.74°C | 115.16V | ||||
| 10 | 34.006A | 8.916A | 9.035A | 2.515A | 499.669 | 88.137% | 2325 RPM | 37.6 dB(A) | 44.23°C | 0.997 |
| 12.129V | 5.050V | 3.287V | 4.965V | 566.922 | 73.58°C | 115.16V | ||||
| 11 | 38.158A | 8.919A | 9.045A | 2.518A | 549.652 | 87.556% | 2375 RPM | 37.7 dB(A) | 46.54°C | 0.997 |
| 12.119V | 5.048V | 3.284V | 4.960V | 627.771 | 78.87°C | 115.16V | ||||
| CL1 | 0.098A | 13.021A | 13.004A | 0.005A | 110.387 | 83.444% | 898 RPM | 13.2 dB(A) | 44.27°C | 0.994 |
| 12.226V | 5.080V | 3.308V | 5.073V | 132.289 | 65.89°C | 115.19V | ||||
| CL2 | 41.619A | 1.004A | 1.001A | 1.002A | 518.247 | 88.692% | 2390 RPM | 37.9 dB(A) | 44.19°C | 0.997 |
| 12.129V | 5.074V | 3.316V | 5.026V | 584.321 | 75.76°C | 115.17V |
The load regulation we measure on each rail is fairly tight, particularly on the 5V rail where SilverStone's SX500-G takes the lead from every other SFX and SFX-L PSU in our comparison charts. Despite the lack of a semi-passive mode, the PSU's fan spins slowly under light loads. Thus, its noise output remains low as well. From our 80% load test and beyond, the fan profile gets more aggressive to protect the PSU from overheating.
With 20% load, the PSU is close to the 80 PLUS Gold level's 87% efficiency requirement. At 50% and full load it easily satisfies the corresponding requirements, despite our grueling test environment. Notice the huge differences between input and output temperatures in the table above. Clearly, the fan does a good job pushing heat from the SX500-G's internals.
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