ok so my moms computer broke awhile back, so she gave it to me. Basically it just sat there with a whole bunch of other computers I didnt really need but where there if I needed something. I just recently decided to work on the thing. The power source was bad so i replaced it, but it still wont turn on. The light is yellow like its on stand by? I'm getting no response from anything. personally I was thinking the jumper switches, but I doubt it.