I am working on a pc running XP pro that has a bad PS. I took one out of another working pc with same voltage values and installed it. When I plug it in and turn it on, I get not response whatever. I put a multimeter on some of the molex connectors, and no power. The mother board looks ok(no bulges on Capacitors), but the system may have other problems since it has been down several months and I don't know any history. What should I look at next? Thanks in advance.