How to test a power supply?
Yesterday my computer just completely shut off while playing a game. When I try to turn it back on lights on the motherboard flash and the fans spin for a moment, then go dead again. If I immediately try to turn it back on again, it does nothing. If I wait a while after that and try again, it does the same turning back on for just a moment and then stopping thing. Does this behavior suggest the problem is with the power supply?
I tried testing it with a multimeter and everything from the power supply disconnected (with the green and black wires shorted with a paper clip), and the voltages were all at the correct level. I understand that the power supply can still fail when everything is plugged in, but I can't find detailed instructions on how to test it this way. The power supply won't stay on long enough for me to test when I try to turn the computer on. Would it be risky to use the paper clip while all the power cords are plugged in? I am better off just buying another power supply and hoping it works, or at this point is it more likely a problem with another component?
Much thanks for any advice.