Rosewill Performance 650 W Power Supply Review

Overload Tests

Before overloading power supplies we always test first if the over current protection (OCP) circuit is active and at what level it is configured. For this test we installed only cables that were connected to the unit’s +12V4 rail (main motherboard cable and peripheral plugs) and increased current to 33 A. The unit didn’t shut down. We repeated the test but now pulling 33 A (the limit from our tester) from +12V3 (EPS12V connector) and again the unit didn’t shut down. This means that either the OCP circuit is disabled or is configured at a value above 33 A.

We could easily overload this unit to the values below. Above that the unit wouldn’t turn on, which is great. The problem was that when overloading the unit it could work only one minute or less before shutting down, just like it happened when we pulled 650 W from it. Anyway, since the overload protection was active, you won’t burn your power supply if you overload it.

Below you can see the maximum amount of current/power we could pull from this unit (but, as explained, the unit would only work one minute or less under this configuration). Noise level was outside specs, at 190 mV on +12V2 input.