|HP still gives free phone support after you buy and even if it is out of warranty. Contact them, I think there is a small reset switch on the bottom of the laptop that they may ask you to reset.|
There are many factors. If the laptop has 2 sticks of ram, take one out and try. Do that with both pieces of ram.
It may be the hard drive or the motherboard....it's hard to tell. You may also want to take some compressed air and blow out your fans, lots of dust on there will cause it to overheat quickly.
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