Well, I lied... My theory is wrong and know my PC is about to drive me up a wall! I have onboard video and when I hit the button (or even do it manually with a screwdriver) every other time it won't...

I am having a similar problem. The weird thing in my situation is that when I get a screw driver and touch the pins to start my pc it comes up everytime. but if I hook up all my front anel connectors...