Home / Tech News / Featured Tech News / Corsair RM850x (2018) PSU Review

Corsair RM850x (2018) PSU Review

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 oscilloscope screenshots that we took during the hold-up time measurements:

The hold-up time is longer than 17ms and the power-ok signal is accurate and right on spot, at 16ms.

Inrush Current

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

The inrush current is quite high with both voltage inputs, especially with 230V.

Load Regulation And Efficiency Measurements

The first set of tests reveals the stability of the voltage rails and the RM850x’s efficiency. The applied load equals (approximately) 10 to 110 percent of the power supplies 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 power supply 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 (RPM) PSU Noise (dB[A]) Temps (In/Out) PF/AC Volts
1 5.225A 1.980A 1.985A 0.994A 84.913 86.974% 0 <6.0 47.19°C 0.970
12.115V 5.054V 3.326V 5.032V 97.630 40.12°C 115.05V
2 11.434A 2.970A 2.977A 1.194A 169.435 90.199% 0 <6.0 48.54°C 0.985
12.116V 5.052V 3.323V 5.028V 187.846 40.99°C 115.05V
3 18.046A 3.466A 3.464A 1.394A 254.532 91.416% 0 <6.0 49.23°C 0.991
12.109V 5.051V 3.321V 5.023V 278.433 41.17°C 115.05V
4 24.673A 3.962A 3.978A 1.595A 339.754 91.411% 0 <6.0 50.97°C 0.988
12.100V 5.050V 3.318V 5.017V 371.676 41.78°C 115.05V
5 30.991A 4.955A 4.977A 1.796A 425.070 90.984% 610 10.2 41.98°C 0.989
12.086V 5.047V 3.316V 5.012V 467.194 51.88°C 115.05V
6 37.258A 5.948A 5.977A 1.998A 509.599 90.471% 610 10.2 42.61°C 0.990
12.072V 5.046V 3.313V 5.007V 563.272 53.01°C 115.05V
7 43.589A 6.942A 6.978A 2.200A 594.887 89.808% 610 10.2 43.30°C 0.991
12.062V 5.044V 3.310V 5.002V 662.398 54.30°C 115.05V
8 49.928A 7.935A 7.982A 2.402A 680.257 88.988% 888 22.2 43.90°C 0.993
12.054V 5.043V 3.308V 4.998V 764.437 55.60°C 115.04V
9 56.673A 8.434A 8.472A 2.402A 765.203 88.194% 1130 30.3 44.46°C 0.994
12.046V 5.041V 3.305V 4.998V 867.641 56.50°C 115.04V
10 63.158A 8.931A 8.994A 3.013A 850.023 87.226% 1415 36.7 46.20°C 0.995
12.038V 5.040V 3.303V 4.981V 974.511 58.61°C 115.04V
11 70.244A 8.935A 8.998A 3.014A 934.759 86.187% 1440 37.1 46.71°C 0.996
12.030V 5.038V 3.301V 4.979V 1084.566 59.59°C 115.03V
CL1 0.146A 18.004A 17.999A 0.000A 152.460 81.936% 714 16.5 41.96°C 0.985
12.097V 5.053V 3.318V 5.102V 186.071 51.73°C 115.06V
CL2 70.846A 1.000A 1.000A 1.000A 866.348 87.734% 1300 34.5 46.78°C 0.995
12.040V 5.041V 3.306V 5.015V 987.473 58.74°C 115.04V

The load regulation is tight on all rails and the fan profile is super relaxed even under extremely stressful conditions. Moreover, the semi-passive operation lasts for quite long and doesn’t seem to be affected by high operating temperatures. Although there are no heatsinks in the secondary side, CWT’s platform doesn’t seem to have any problem at all under increased temperatures.

The 80 PLUS Gold requirements with 20%, 50% and full load are easily met even with the tough conditions that we apply. This is something that we don’t see everyday.

Become a Patron!

Check Also

Valve announces Steam Open World Sale event for May

Over the last few years, developers from Valve’s SteamWorks forum have regularly leaked upcoming sales …