search for that and use my username. I asked this a few months back. But you run a paperclip across a power supply (computer power suppy) and you can test it that way.
if your using a power supply. on the 20/24 pin molex mobo connector. cut the green wire and any black wire on the same connector and twist or tape them together.
then just cut the yellow wire and put it in the + cut the black wire put it in the - and then cut the red wire (5v) and put it in the REM.
or if the psu has a switch on it. not like a little switch on the back by the inlet. it is on a wire. then you can just use that