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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 power-good signal is accurate. This is what we expect from a Seasonic PSU.
Inrush Current
For details on our inrush current testing, please click here.
With 115V, the inrush current is low. However, the situation turns with 230V input.
Load Regulation And Efficiency Measurements
The first set of tests reveals the stability of the voltage rails and the SSR-850FX'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 | 5.222A | 1.996A | 1.987A | 0.985A | 84.992 | 86.748% | 621 RPM | 11.6 dB(A) | 41.65°C | 0.973 |
| 12.137V | 5.010V | 3.327V | 5.078V | 97.976 | 47.59°C | 115.27V | ||||
| 2 | 11.485A | 2.997A | 2.979A | 1.184A | 170.301 | 90.194% | 565 RPM | 10.7 dB(A) | 38.83°C | 0.988 |
| 12.136V | 5.009V | 3.325V | 5.069V | 188.816 | 47.93°C | 115.17V | ||||
| 3 | 18.076A | 3.497A | 3.490A | 1.384A | 255.483 | 91.014% | 550 RPM | 10.4 dB(A) | 39.01°C | 0.990 |
| 12.136V | 5.008V | 3.323V | 5.059V | 280.706 | 48.41°C | 115.15V | ||||
| 4 | 24.667A | 3.997A | 3.973A | 1.585A | 340.575 | 91.022% | 550 RPM | 10.4 dB(A) | 39.57°C | 0.991 |
| 12.136V | 5.007V | 3.322V | 5.050V | 374.169 | 49.23°C | 115.03V | ||||
| 5 | 30.861A | 4.998A | 4.968A | 1.786A | 425.082 | 90.655% | 560 RPM | 10.5 dB(A) | 40.75°C | 0.990 |
| 12.137V | 5.006V | 3.321V | 5.041V | 468.903 | 50.75°C | 114.91V | ||||
| 6 | 37.117A | 5.997A | 5.965A | 1.988A | 510.384 | 90.095% | 880 RPM | 20.6 dB(A) | 41.79°C | 0.991 |
| 12.139V | 5.005V | 3.320V | 5.031V | 566.497 | 52.22°C | 114.88V | ||||
| 7 | 43.348A | 6.997A | 6.961A | 2.192A | 595.278 | 89.427% | 1333 RPM | 31.4 dB(A) | 42.33°C | 0.991 |
| 12.138V | 5.004V | 3.319V | 5.020V | 665.660 | 52.93°C | 114.75V | ||||
| 8 | 49.587A | 7.998A | 7.962A | 2.395A | 680.212 | 88.693% | 1984 RPM | 41.5 dB(A) | 42.93°C | 0.992 |
| 12.136V | 5.003V | 3.317V | 5.011V | 766.925 | 53.79°C | 114.72V | ||||
| 9 | 56.248A | 8.499A | 8.474A | 2.398A | 765.241 | 87.942% | 2310 RPM | 45.1 dB(A) | 44.02°C | 0.992 |
| 12.136V | 5.002V | 3.316V | 5.006V | 870.166 | 55.12°C | 114.58V | ||||
| 10 | 62.643A | 9.000A | 8.958A | 3.009A | 849.956 | 87.009% | 2320 RPM | 45.2 dB(A) | 45.40°C | 0.993 |
| 12.136V | 5.002V | 3.315V | 4.987V | 976.857 | 56.83°C | 114.43V | ||||
| 11 | 69.683A | 9.000A | 8.962A | 3.012A | 935.525 | 85.851% | 2320 RPM | 45.2 dB(A) | 47.19°C | 0.993 |
| 12.138V | 5.001V | 3.314V | 4.981V | 1089.714 | 58.87°C | 114.39V | ||||
| CL1 | 0.159A | 12.001A | 12.000A | 0.001A | 101.985 | 85.242% | 560 RPM | 10.5 dB(A) | 43.42°C | 0.983 |
| 12.145V | 5.008V | 3.329V | 5.092V | 119.642 | 53.02°C | 115.24V | ||||
| CL2 | 70.008A | 1.002A | 1.001A | 1.001A | 863.063 | 87.262% | 2320 RPM | 45.2 dB(A) | 45.75°C | 0.993 |
| 12.137V | 5.004V | 3.315V | 5.039V | 989.045 | 56.15°C | 114.43V |
On every rail except the 5VSB one (which is still within 3%), the load regulation we observe is extremely tight. Seasonic's new platform achieves excellent performance in this discipline, despite its budget orientation. The measured efficiency levels are pretty good as well, while the fan profile is relaxed. It's only when you push the PSU hard, under 80% of its maximum-rated-capacity load and high operating temperatures, that the fan spins at full speed.
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