What is your voltage on the overclock and what did you use to overclock it? Also what is your usage at idle? Do the spikes still happen when the GPU is idle. I would check processes running in the background you might have a bitcoin miner running that is using the GPU.

I am not running anything like that in the background. However, from time to time, the usage does spike to 48% even at idle. As a matter of fact, it is doing it right now. I do have HWinfo64 and Afterburner both monitoring at the same time, maybe they conflict? However, as I've stated this has not happen in other games.

Try and disable ULPS and reboot and see what happens?

Have you raised the power limiter to +20%?

The Fixer (ironically named) http://www.youtube.com/watch?v=eH6XayaLTw8 But you have an AMD card anyways so I wouldn't worry much about him ever getting near that card.