Dell :: M1730 X9000 CPU Bottleneck?

so story is, i jump on a new game called Demigod, cpu running at 2.8ghz , after about 5-10mins of playing, i notice both my cores are running at 100% and the game lags like crazy, frame rate goes down really bad.

so i figure, hm, cpu bottleneck for a game.. strange.. lets have some overclock fun - i go ahead and set my x9000 to 3.4ghz, now the game runs great, my cpu cores dont reach 100% and the frame rate is great, all is good and great. only problem with running at 3.4ghz is that after about 30mins-1hr of playing, my m1730 powers down due to what i can assume to be overheating