|What symptoms are you getting? Does the computer start at all? Any fans/lights? Anything on the screen? You have to be more specific to be able to track down the part that's failed, but as a general rule it's anything with a fan or heatsink.|
Computers are designed to be running 24/7 so 10 hours should not cause a problem. You need to occasionally check for dust build-up within the case - blow it away with compressed air. If it still gets hot then look at replacing/adding fans.
"I've always been mad, I know I've been mad, like the most of us..." Pink Floyd