I had this happen once too. Was upgrading my machine. Swapped out the case, the motherboard, upgraded the fans and upgraded the CPU heatsink. Plugged it in and

I had this happen once too. Was upgrading my machine. Swapped out the case, the motherboard, upgraded the fans and upgraded the CPU heatsink. Plugged it in and all 4 3TB WD Green drives were on fire within seconds and my PSU was smoking. After getting it under control, none of the hard drives nor the SSD would power on any more, my PSU was shot, my motherboard had scorchmarks, and one of the new fans no longer worked. I was only able to save the GPU, the heatsink, memory, fans minus the one, CPU, and the blu-ray drive. I never figured out for sure, but I think I shorted out my cheap PSU when moving it; I probably should have bought a new one to start with but thought that was an easy place to save money. Ended up costing my like $900 and a ton of headaches. Go figure.