Hi everyone, my fiance's computer at the moment is having some problems. Its a custom built computer thats she has had for 4 year now. And since then she's had no problems with it. Well today we wake up and turn on her computer and for no reason it turns back off by itself after a few seconds. In the beginning it looks like its about to turn on but then out of no where it will shut its self off. And if I try to turn it back on again with the power button it just turns off even quicker. But if I let it sit a bit it start powering up longer and then just dies agian. I can't even get into the windows picture on the monitor, nor see it even start loading on the Monitor. All the fans spin fine, we blew out all the dust from it and that didn't work. I'm thinking it may be the Power supply or the mother board. What do you guys think?

borrow a power supply from a friend..clean the dust on the processor fan.. check if it will help

same advice as above here. Try blowing off the dust in the CPU and check if all the fans are moving freely. looks like overheating due to dust or fan failure.