Riotoro Onyx 650W PSU Review

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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 measured is ridiculously low. GW uses low-capacity bulk caps to save a few bucks, resulting in a hold-up time lower than 8ms. As a point of reference, the ATX spec requires at least 17ms. This is a major downside for this PSU. Great Wall should have used bulk caps with at least double the capacity.

Inrush Current

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

The small NTC thermistor does an average job in restricting the inrush currents.

Load Regulation And Efficiency Measurements

The first set of tests reveals the stability of the voltage rails and the PR-BP0650-SM'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 SpeedFan NoiseTemps (In/Out)PF/AC Volts
13.595A1.985A1.989A0.984A64.74983.209%1560 RPM32.8 dB(A)38.58°C0.974
12.017V5.028V3.316V5.053V77.81539.50°C115.16V
28.239A2.982A2.987A1.190A129.73687.792%1595 RPM33.6 dB(A)38.99°C0.968
12.003V5.018V3.308V5.040V147.77739.94°C115.15V
313.242A3.497A3.513A1.390A194.88388.790%1680 RPM35.2 dB(A)39.80°C0.976
11.991V5.010V3.299V5.028V219.48741.08°C115.15V
418.242A3.998A4.007A1.595A259.72488.914%1765 RPM36.6 dB(A)39.87°C0.981
11.980V5.002V3.292V5.013V292.10741.43°C115.15V
522.909A5.008A5.027A1.800A324.68788.578%1870 RPM38.9 dB(A)40.33°C0.984
11.969V4.990V3.283V4.998V366.55441.92°C115.14V
627.586A6.026A6.045A2.004A389.65788.070%1870 RPM38.9 dB(A)40.92°C0.986
11.958V4.980V3.273V4.984V442.44042.79°C115.14V
732.272A7.040A7.075A2.209A454.57987.360%1870 RPM38.9 dB(A)42.01°C0.987
11.946V4.970V3.264V4.969V520.35444.27°C115.14V
836.960A8.068A8.109A2.419A519.50086.465%1870 RPM38.9 dB(A)43.10°C0.989
11.935V4.960V3.254V4.952V600.82345.68°C115.14V
942.091A8.584A8.654A2.425A584.51685.561%1870 RPM38.9 dB(A)44.05°C0.991
11.925V4.952V3.246V4.941V683.15547.14°C115.14V
1046.979A9.103A9.178A3.046A649.32584.361%1870 RPM38.9 dB(A)45.22°C0.992
11.913V4.943V3.236V4.914V769.69548.96°C115.14V
1152.470A9.122A9.198A3.053A714.18283.258%1870 RPM38.9 dB(A)45.94°C0.992
11.902V4.934V3.229V4.905V857.78949.96°C115.14V
CL10.099A16.027A16.004A0.000A133.60881.588%1870 RPM38.9 dB(A)42.75°C0.972
11.989V4.987V3.280V5.035V163.75944.86°C115.18V
CL254.112A1.002A1.001A1.001A658.40485.081%1870 RPM38.9 dB(A)44.49°C0.992
11.923V4.966V3.260V4.982V773.85847.66°C115.15V

Load regulation at +12V is tight enough for this category. It's merely decent on the other rails, since at 5V and 3.3V our measurements fall within 3%.

Despite the 40°C rating, this PSU doesn't seem to have a problem delivering its full load (and even more) under very high ambient temperatures and for prolonged periods of time. The fan profile is quite aggressive at high temperatures and loads though; from our fifth test onward, the fan spins at full speed. Nonetheless, the output noise is below 40 dB(A), so it isn't that loud.

Great Wall's platform easily satisfies the 80 PLUS Bronze specification's requirements since it is based on a modern design.


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Contributing Editor

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