Possible but not a practise to copy dark06 (A Multimeter gives a resistance "load" to get a true reading as the guys at Overclockers do) many PSUs have a fan if the fan spins and you can open and close an Optical Drive your PSU is working, (just a question why do you want to test a PSU "out of case, not connected to a Motherboard") ? , Oh and how did your loading of XP go ?

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