Hmm, at first i thought you meant the switch, which would men you have the hader on wrong. But since this is from the OS I have to think that when the board receives the signal to reboot, instead of shutting off the power and then turning it back on, it just shuts it off. Since under the ATX standard the board controls power on/off, this is a very real possibility, which would mean you might need to RMA the board. I'm not sure if BIOS would affect it as I'm pretty sure its just a hardwired thing.