How do you know if a motherboard is dead because I've had problems with my old computer were it kept on restarting after every 5 seconds. The CD Drive was making the sound it usually does when I turn the computer on, it just did it every 5 seconds... The monitor wouldn't even try to come onso I wouldn't even be able to get into BIOS. The lights on the keyboard and mouse wouldn't come on either. I've already bought a new computer (it was time to get a new one anyways...) but I was just wondering what would cause a computer to restart every 5 seconds like that and what I should do if it ever happens again.