I've posted a thread like this before, but didn't know the problem. I'm convinced that it's an overheating problem, it's just I don't know where. I was ripping CD's to my computer yesterday, and it shut down twice. Then later that night, I was playing Halo, and it did it again. The chipset only has a passive heatsink, and the sensor reads it at 70C. I can't replace it because the graphics card is in the way. My Proc. usually reads about 34C - 42C. Here are the specs:

Gigabyte GA-K8N-SLI Mobo
AMD Anthlon64 3200+ 939
GeForce 7800GT Graphics Card
120GB WD HDD

Anyway, I'm pushing towards the overheating possibility. It's just I'm not entirely sure of what to do. My case is getting the best ventalation it can, which is pretty good. The only thing I can think of to do is get a new mobo. If anybody has any ideas, I'd appreciate it. Thanks.