The board would power on but not POST. It was unresponsive to the power button once powered up, but holding it down for several seconds would cause the board to power off. It was completely unresponsive otherwise.
The problem was solved by removing the heatsink and re-flowing the Nvidia northbridge with a hot-air soldering station. Using an oven to repair this board is not recommended due to the many small electrolytic capacitors mounted on the board.