Dell computer on standby

I have a Deel Dimension 8100 computer that is locked in the standby mode. When the computer is turned on the power switch light goes to orange immediately. the hard drive, floppy, and CD drives are being checked by the system and seem to be fine. When the reset button is pushed, the power button momentarily flashes to green, then back to orange. Could the motherboard have been fried or is there something else wrong?