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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.
Our hold-up time tests are described in detail here.
The hold-up time we measure is accurate, as is the power-good signal.
For details on our inrush current testing, please click here.
Inrush current is low with both voltage inputs.
Load Regulation And Efficiency Measurements
The first set of tests reveals the stability of the voltage rails and the HCG850’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||5.199A||1.984A||1.976A||0.986A||84.852||86.522%||478 RPM||9.6 dB(A)||38.13°C||0.969|
|2||11.414A||2.968A||2.967A||1.186A||169.719||89.731%||496 RPM||9.8 dB(A)||38.87°C||0.983|
|3||17.989A||3.473A||3.475A||1.385A||254.940||90.470%||512 RPM||11.5 dB(A)||39.34°C||0.986|
|4||24.544A||3.963A||3.960A||1.586A||339.758||90.397%||515 RPM||11.5 dB(A)||39.86°C||0.988|
|5||30.752A||4.966A||4.953A||1.786A||424.648||89.976%||525 RPM||11.7 dB(A)||40.19°C||0.988|
|6||36.975A||5.953A||5.950A||1.991A||509.639||89.328%||823 RPM||20.5 dB(A)||41.32°C||0.988|
|7||43.194A||6.954A||6.945A||2.196A||594.588||88.574%||1185 RPM||30.2 dB(A)||42.02°C||0.989|
|8||49.424A||7.948A||7.945A||2.400A||679.571||87.755%||1646 RPM||40.5 dB(A)||43.61°C||0.990|
|9||56.066A||8.454A||8.458A||2.400A||764.513||86.908%||2053 RPM||46.0 dB(A)||44.65°C||0.990|
|10||62.450A||8.953A||8.947A||3.015A||849.284||85.787%||2130 RPM||49.1 dB(A)||44.98°C||0.991|
|11||69.430A||8.956A||8.952A||3.017A||934.187||84.431%||2150 RPM||49.2 dB(A)||46.28°C||0.992|
|CL1||0.100A||12.013A||12.006A||0.005A||101.864||84.708%||520 RPM||11.6 dB(A)||41.49°C||0.978|
|CL2||69.958A||1.002A||1.002A||1.002A||864.308||85.962%||2140 RPM||49.1 dB(A)||45.97°C||0.991|
Load regulation on the +12V rail is flawless, and it's fairly tight on the minor rails. The HCG850's efficiency satisfies the 80 PLUS Gold standard's requirements with 20% of its maximum-rated load, it's a hair away with 50% load, and the PSU falls notably under its 87% requirement with full load. Then again, we run our tests at a much higher ambient temperature than the 80 PLUS organization.
At up to 60% of its maximum load, this PSU is downright quiet. Afterward, it starts to make its presence known. The HCG850 is particularly loud in the last three tests, where its fan spins at high speeds.
MORE: Best Power Supplies
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Aris Mpitziopoulos is a Contributing Editor at Tom's Hardware US, covering PSUs.
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