well all computers will eventually crash(or die) when they get too hot... on another note, hsi system doesn't have the shutdown feature.
my bro had this problem. he just installed a new video card and his PSU was 3 years old maybe and it couldn't handle that new vid card, it crapped out on him and shorted his mobo, fried his ram and his HDD's + more. he had to basically buy a new PC