It turns off usually within minutes of originally being turned on. All hardware tests come back that show things such as the GPU, CPU, RAM, and Hard Drives are OK. I'm thinking it's either a bad PSU or Mobo. It's worth noting I put a new GPU and some additional RAM in a few days before the problems started, but I removed the additional RAM I put in and the problem still occurs, and tests show that my GPU is OK. What sounds like the problem?