Before performing our overload tests we always like to test first if the over current protection (OCP) circuit is really active and at what level it is configured.

We configured +12V1 input from our load tester with a low current (1 A) and increased current on +12V2 input (which was connected to the power supply +12V2 rail) until the power shut down. This happened only when we tried to pull more than 22 A. So OCP was active and configured the way we like: very close to the limit printed on the power supply label (20 A on this case).

Here is the biggest difference between MSI Turbostream 600 W and Rosewill RD600N-2DB-SL. Even though they are the same power supply with a different set of fans and different sticker, on Rosewill’s model the OCP is either disabled or configured at a value that is too high. Read its review for further information.

The maximum amount of power we could pull from MSI Turbostream with it still working inside ATX specs can be found below. Above that voltages would go out of the expected range. As you can see this is more than we could pull with the model labeled by Rosewill (746 W vs. 675 W). Noise level was still inside ATX specs (83 mV at +12 V, 37 mV at +5 V and 29 mV at +3.3 V).

Of course you should not run this unit above its labeled power, as efficiency drops a lot: see how it dropped to 75% during this test.