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.
Our hold-up time tests are described in detail here.
As we expected given the bulk capacitors' low capacity, measured hold-up time didn't meet the ATX specification's requirements. There simply wasn't enough space on the PCB for larger caps, which would have also had a negative impact on efficiency. The trade-off could have cost Rosewill its 80 PLUS Gold rating.
For details on our inrush current testing, please click here.
This platform's small NTC thermistor results in higher inrush currents, taxing your home's electrical infrastructure.
Load Regulation And Efficiency Measurements
The first set of tests exposes the stability of the voltage rails and the PSU's efficiency. The applied load equals (approximately) 10 to 110 percent of the supply's maximum 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 0.10A. This benchmark reveals whether a PSU is Haswell-ready 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||PowerDC/AC (W)||Efficiency%||Fan Speed (RPM)||Fan Noise dB(A)||Temp In/Out(°C)||PF/AC(V)|
Our load regulation measurements show that Rosewill fails to match the competition. This doesn't surprise us, particularly when it comes to the +12V rail, because we haven't tested any ACRF topology-based PSU with great load regulation.
Under a 20 percent load, the PSU easily satisfies the 80 PLUS Gold efficiency requirement (87 percent). With a 50 percent load applied, the margin is a lot closer. But given our warm ambient test environment, we'll give the PSU a pass on this one. However, under a full load, the measured efficiency level was significantly lower than the permissible minimum. Obviously our 48°C operating temperature played a big part in this.
The big Capstone unit proved to be very noisy under tough conditions. During the first two tests, the fan rotated slowly. However, it sped up quickly, and with 70 percent load applied, acoustic output approached 52 dB(A). If you need a quiet PSU, avoid this one.