check to make sure you have all the thermal sensor's hooked up correctly. They will shut it down right now if they sense it is getting to hot. Also does the case have a intrusion sensor, that could shut it off possibly
Also check you fan/heatsink is properly contacting the chip and the fan is running, they will overheat right now.
Do you have your jumpers set correctly for the chip you have.
Also check you fan/heatsink is properly contacting the chip and the fan is running, they will overheat right now.
Do you have your jumpers set correctly for the chip you have.