Okay, so I put my computer on standby (winxp) and decided to go out for 3 hours. Now I come back and attempted to move my mouse and punch some keys to start my computer back up. I look at it and see no lights so I thought somebody turned off my computer, so I hit the power button. Nothing happens. I check the power to see if its connected properly; it is. Then I checked the main power switch in the back and it was switched on. I looked inside and I see a light on the motherboard. So power is going through right? But why is it that my computer is refusing to start up? I switched off the power switch and switched it back on and i hear like a really really small sound, which sounds like it was going to start up but didn't. Could somebody please give me a hand in solving my problem and what i could do to fix it. Thank you.