I recently upgraded the CPU yesterday and the computer was running in perfect condition yesterday and today. I was playing a game and about a minute after I was done playing the game and was exited onto my desktop... my computer powered off. So I waited about 30 seconds and turned it back on... it didn't turn on. The speaker that will beep never beeped- and the only thing that happens is the LED lights will dimly turn on. I had to turn my PC off by flicking the switch on the power box in the back. But no display- no nothing. The only fan that will turn when it is on is the rear fan and it barely spins. Aside from that- only LED lights from my fans will turn on and its dim. Is it a power box failure? My computer is custom built! NEWEST CPU: AMD FX 8350 (Previous one was a 6200) Motherboard: Gigabyte GA-970A-UD3 RAM: Crucial Ballistix Spot 16GB Storage: WD RE2-GP 1TB 3.5" 7200RPM GPU: Sapphire Radeon HD 7870 GHz Edition 2GB GDDR5 Case: Sentey GS-6400 Arvina ATX Full Tower Windows 7 Home Premium I only know my power supply is 550W. I had a PC repair place swap the one I have now with one that was defective back when I was building the thing and had issues.