+1 for learning how to use a DMM.
@OP: If you trouble shoot PCs, in certain cases, a multi meter WILL be a valuable tool to have. This is VERY true when you are trying to check for a bad PSU. When the PSU is jumped, and voltages are tested, if the rails are VERY low (ie +12rail showing 9v,etc) or too high (+12 showing 14v,etc) it is a good sign that the PSU is bad, saved me a couple of hours of work troubleshooting stupid PSU problems.