Corsair SF450 Platinum SFX PSU Review: Best of the Best

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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 SF450 Platinum's hold-up time is higher than 17ms. However, its power-good signal doesn't reach 16ms, as the ATX spec requires. For us, what matters most is that it is accurate.

Inrush Current

For details on our inrush current testing, please click here.

Inrush current is low enough with 115V and more than double with 230V input.

Load Regulation And Efficiency Measurements

The first set of tests reveals the stability of the voltage rails and the SF450’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.

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Test #12V5V3.3V5VSBDC/AC (Watts)EfficiencyFan SpeedPSU NoiseTemps (In/Out)PF/AC Volts
11.925A1.981A1.969A0.995A44.85984.997%0 RPM<6.0 dB(A)44.32°C0.870
24.841A2.971A2.955A1.195A89.38189.567%0 RPM<6.0 dB(A)45.61°C0.937
38.152A3.467A3.435A1.396A134.48591.120%0 RPM<6.0 dB(A)46.63°C0.960
411.467A3.963A3.944A1.597A179.68591.657%1311 RPM13.8 dB(A)41.86°C0.974
514.450A4.953A4.931A1.799A224.98891.785%1393 RPM15.7 dB(A)42.15°C0.981
617.362A5.946A5.918A2.001A269.48691.049%1547 RPM18.9 dB(A)42.66°C0.877
720.342A6.938A6.906A2.204A314.78591.078%1728 RPM22.0 dB(A)43.00°C0.987
823.326A7.931A7.894A2.407A360.10690.707%1934 RPM25.3 dB(A)43.94°C0.989
926.707A8.427A8.376A2.408A405.00490.376%2174 RPM28.3 dB(A)44.52°C0.990
1030.025A8.926A8.887A2.510A449.70689.918%2706 RPM34.5 dB(A)45.67°C0.991
1133.744A8.926A8.892A2.512A494.51789.481%3184 RPM38.7 dB(A)46.88°C0.992
CL10.138A12.002A11.999A0.000A102.47686.890%742 RPM6.5 dB(A)42.21°C0.948
CL237.509A1.002A1.001A1.000A466.10290.568%2648 RPM34.3 dB(A)45.90°C0.991

The SF450 Platinum's load regulation is amazing on every rail. Great Wall's engineers did a superb job optimizing for this series of tests. Better still, the fan profile operates conservatively. We pushed the PSU hard to get its fan spinning at close to 3200 RPM, and it still didn't break the 40 dB(A) threshold. It is very hard to make such a tiny PSU quiet, but an efficient platform surely helps.

Speaking of efficiency, with 20% and 50% load, the SF450 lands close to the 80 PLUS Platinum specification's requirements. Under full load, it easily passes the 89% mark. Efficiency levels would be even higher at lower ambient temperatures.

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Contributing Editor

Aris Mpitziopoulos is a Contributing Editor at Tom's Hardware US, covering PSUs.