Something's not connected up properly. And to clear the CMOS you unplug the power supply, remove the button cell battery from the board, and short the battery terminals with a screwdriver (Or press the power button a few times, to force the circuit to run out of power.
Make sure your processor is properly seated in the socket, and that if the PSU has a hard switch in the back that it's flipped on, and plugged into the main ATX power socket, the CPU power, and the GPU.