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.
Not only is the RX-700AT's hold-up time lower than 17ms, but its power-good signal drops after the rails go out of spec. This is a troubling issue to have.
For details on our inrush current testing, please click here.
Inrush current is very high with both voltage inputs. Raidmax should add an NTC thermistor and a bypass relay to bring our result down during the PSU's cold start-up.
Load Regulation And Efficiency Measurements
The first set of tests reveals the stability of the voltage rails and the PSU's efficiency. The applied load equals (approximately) 10 to 110 percent of the maximum load the supply can handle, 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 test 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||DC/AC (Watts)||Efficiency||Fan Speed (RPM)||Noise (dB[A])||Temps (In/Out)||PF/AC Volts|
Load regulation is tight at +12V and 5V, satisfactory at 3.3V and super tight at 5VSB. As far as efficiency goes, the RX-700AT meets the Titanium requirements at 20 percent and full load, comes close to the 90 percent mark under 10 percent load and is further off with 50 percent load. Obviously, a high ambient temperature is the main culprit preventing higher efficiency scores. Nonetheless, the PSU has absolutely no problem delivering more than its full power at 47 °C.
The fan profile is aggressive, and in most of the load tests the fan spins at top speed. It's only during the first two tests, with 10 percent and 20 percent load, that the fan is inaudible. Given this unit's high efficiency, we believe that the fan profile should be much more relaxed.