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 measured is very long, exceeding the ATX spec's requirements by far. Corsair's power-good signal is also accurate, since it drops before the rails go out of spec.
For details on our inrush current testing, please click here.
We observed low inrush current levels, especially with 115V input. That's excellent, given the HX1200's high capacity.
Load Regulation And Efficiency Measurements
The first set of tests reveals the stability of the voltage rails and the HX1200'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||Fan Noise||Temps (In/Out)||PF/AC Volts|
|1||8.072A||1.986A||1.985A||0.996A||119.782||88.561%||0 RPM||<6.0 dB(A)||49.84°C||0.985|
|2||17.182A||2.976A||2.981A||1.196A||239.633||91.874%||0 RPM||<6.0 dB(A)||51.02°C||0.994|
|3||26.674A||3.480A||3.496A||1.395A||359.827||92.470%||0 RPM||<6.0 dB(A)||52.21°C||0.996|
|4||36.162A||3.982A||3.979A||1.600A||479.630||92.571%||0 RPM||<6.0 dB(A)||53.55°C||0.998|
|5||45.348A||4.979A||4.978A||1.802A||599.553||92.106%||0 RPM||<6.0 dB(A)||54.95°C||0.998|
|6||54.560A||5.988A||5.985A||2.005A||719.431||91.405%||700 RPM||19.0 dB(A)||41.22°C||0.998|
|7||63.566A||6.992A||6.986A||2.207A||839.318||90.584%||710 RPM||19.2 dB(A)||42.71°C||0.998|
|8||72.793A||7.998A||7.992A||2.410A||959.262||90.006%||830 RPM||21.8 dB(A)||43.66°C||0.999|
|9||82.456A||8.504A||8.514A||2.413A||1079.235||89.225%||1165 RPM||30.9 dB(A)||44.56°C||0.999|
|10||91.696A||9.023A||9.007A||3.541A||1199.085||88.348%||1310 RPM||34.5 dB(A)||45.36°C||0.999|
|11||101.758A||9.032A||9.017A||3.545A||1319.046||87.460%||1525 RPM||38.6 dB(A)||45.51°C||0.999|
|CL1||0.099A||18.028A||18.003A||0.004A||151.890||84.244%||730 RPM||19.5 dB(A)||43.86°C||0.990|
|CL2||99.934A||1.003A||1.002A||1.002A||1219.611||88.433%||1345 RPM||34.7 dB(A)||45.66°C||0.999|
Load regulation on every rail is tight, approaching the HX1200i's performance. That's to be expected, since both PSUs are based on the same platform.
The fan's noise is kept very low, even under high temperatures. It helps that the passive mode lasts a long time, and that the fan only speeds way up during our full-load and overload tests. In no case did we record a >40 dB(A) reading, which is amazing for a 1200W PSU.
Given its 80 PLUS Platinum badge, we expect this PSU to deliver at least 90% efficiency with 20% load, 92% with 50% load, and 89% at full load. As you can see from the table above, only the last condition isn't satisfied, mostly because of the high ambient temperature we test at. In comparison, the 80 PLUS organization tests at unrealistically low ambient temps of 23°C +/-5°C.
In any case, this is a solid-performing PSU that will easily deliver its full power for prolonged periods, even under high operating temperatures. At the same time, its fan won't be a major noise source.
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