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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 measured hold-up time is significantly longer than the ATX spec's minimum requirement, so everything's fine here. The same applies to the power-good signal. Disturbingly, we've seen a lot of high-end PSUs fail these crucial tests, including the SuperNOVA 850 P2. It's obviously a relief that at least the top Leadex platform isn't plagued by the same issues.
Inrush Current
For details on our inrush current testing, please click here.
The inrush current with 115V is low for a 850W PSU, while with 230V is normal.
Load Regulation And Efficiency Measurements
The first set of tests explores voltage rail stability and efficiency. The applied load equals (approximately) 10 to 110 percent of the supply's maximum 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 0.10A. 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 (RPM) | Noise (dB[A]) | Temps (In/Out) | PF/AC Volts |
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 5.169A | 1.983A | 1.988A | 0.981A | 84.78 | 89.79% | 0 | 0 | 45.43 °C | 0.945 |
| 12.226V | 5.040V | 3.318V | 5.091V | 94.42 | 37.55 °C | 115.1V | ||||
| 2 | 11.360A | 2.969A | 2.984A | 1.180A | 169.64 | 92.76% | 0 | 0 | 47.18 °C | 0.976 |
| 12.219V | 5.034V | 3.315V | 5.081V | 182.88 | 38.55 °C | 115.1V | ||||
| 3 | 17.918A | 3.478A | 3.499A | 1.375A | 254.87 | 93.70% | 0 | 0 | 48.24 °C | 0.988 |
| 12.212V | 5.029V | 3.312V | 5.074V | 272.00 | 39.40 °C | 115.1V | ||||
| 4 | 24.464A | 3.981A | 3.989A | 1.575A | 339.76 | 93.83% | 0 | 0 | 49.62 °C | 0.994 |
| 12.205V | 5.024V | 3.308V | 5.066V | 362.10 | 40.26 °C | 115.1V | ||||
| 5 | 30.669A | 4.978A | 4.990A | 1.775A | 424.61 | 93.59% | 0 | 0 | 51.30 °C | 0.995 |
| 12.200V | 5.018V | 3.305V | 5.058V | 453.68 | 41.19 °C | 115.1V | ||||
| 6 | 36.898A | 5.983A | 5.998A | 1.980A | 509.71 | 93.20% | 0 | 0 | 54.06 °C | 0.996 |
| 12.194V | 5.012V | 3.300V | 5.049V | 546.90 | 42.10 °C | 115.1V | ||||
| 7 | 43.120A | 6.997A | 7.008A | 2.180A | 594.61 | 92.68% | 620 | 20.8 | 43.67 °C | 0.997 |
| 12.187V | 5.005V | 3.296V | 5.040V | 641.59 | 58.36 °C | 115.1V | ||||
| 8 | 49.369A | 8.002A | 8.019A | 2.385A | 679.56 | 92.09% | 940 | 30.2 | 44.94 °C | 0.998 |
| 12.177V | 4.999V | 3.292V | 5.030V | 737.90 | 55.46 °C | 115.1V | ||||
| 9 | 56.059A | 8.507A | 8.548A | 2.385A | 764.58 | 91.48% | 940 | 30.2 | 45.28 °C | 0.998 |
| 12.166V | 4.994V | 3.287V | 5.026V | 835.79 | 56.12 °C | 115.1V | ||||
| 10 | 62.699A | 9.028A | 9.054A | 2.488A | 849.45 | 90.92% | 1315 | 41.7 | 47.19 °C | 0.998 |
| 12.157V | 4.989V | 3.279V | 5.020V | 934.29 | 58.26 °C | 115.1V | ||||
| 11 | 69.732A | 9.031A | 9.059A | 2.490A | 934.38 | 90.54% | 1315 | 41.7 | 47.68 °C | 0.998 |
| 12.149V | 4.985V | 3.278V | 5.016V | 1032.05 | 59.26 °C | 115.1V | ||||
| CL1 | 0.099A | 12.009A | 12.005A | 0.003A | 101.14 | 86.26% | 940 | 30.2 | 45.29 °C | 0.962 |
| 12.232V | 5.017V | 3.304V | 5.096V | 117.25 | 53.53 °C | 115.1V | ||||
| CL2 | 70.794A | 1.002A | 1.003A | 1.002A | 873.67 | 91.43% | 1315 | 41.7 | 46.89 °C | 0.998 |
| 12.152V | 5.006V | 3.284V | 5.059V | 955.57 | 55.05 °C | 115.1V |
Load regulation on the +12V and 5VSB rails is tight. The 5V and 3.3V rails are a little above 1%, so they're pretty good. Efficiency is very high in all of the tests, and the PSU satisfies the stringent 80 PLUS Titanium requirements in the 20% and full load tests. It comes close in the 10% and 50% measurements. But given the high temperatures inside our hot-box during testing, we will definitely give the 850 T2 a pass; it rightfully deserves its Titanium badge.
Our readings look good in the noise output benchmarks as well. At up to 60% load, the PSU operates passively. And at up to 90% the fan spins slowly, generating minimal noise. It's only during the full load and overload tests that the fan hits 100% duty cycle and we measure close to 42 dB(A). Under normal operating conditions, though, you won't see the fan spin. When it does start turning, you probably won't hear it.
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