Computer doesn't boot up

Hello,

Yesterday I turned my computer on to check something. Less than 5 minutes after startup my computer suddenly bluescreened, but the blue screen didn't show any text at all, just blue. I forced a power off by switching the mains off. After turning on the computer it powers on, the light on the system unit lights up and the cd reader opens and closes but the keyboard, mouse and monitor don't receive any signal or power whatsoever. I opened up the system unit to have a look. The fans were running fine, but when I took both RAM sticks out and powered on, the mobo didn't make a sound. Tried removing static from the RAM but no results. My computer has already been acting up recently, and the graphics card was recently changed due to the previous card being faulty. Anyone can help me?