I test the pinouts since they're are only 4 BUS (voltages) you can test 12V/5V/2.2V and switched negative (proper voltage I dont know off the top of my head 12V-?) It takes all of twenty seconds and thats only for supplies that are 400W or better anyways, usually aftermarket. Why you'd waste time with handling used product that with fees and whatnot and the chance of bad reviews for DOAs...I won't sell anything I don't have a second one of without a disclosure.