If the fans aren't starting you may have a problem with the power supply or the motherboard, or possibly a loose connection somewhere in the case.
Have you installed or moved any hardware before the problem began or been inside the case for any reason? OR did you move or jar the computer?
In any case, open the computer's case and touch something metal inside the case like the frame with the computer off but it's power plug plugged in so you will be grounded (static electricity can destroy electronic components).
CAREFULLY make sure all connections are tightly made. Press GENTLY to make sure all connections are secure - the connections from the power supply to all internal components, the IDE ribbon connections to the hard drive or the connections to the sata drive if applicable, and all the power connections.
After taking your hand out, press the button to start the computer.
Anything happen? Did the fans turn on/ Do you see any leds light up on the motherboard? Anything?
Edited by Enthusiast, 13 November 2006 - 11:54 PM.