i believe your problem in ethier the cpu/proccessor is overheating or you might have some virus, to find virus start win in safe node: power the computer and immediately keep pressing f8 and in safe mode try to install anivirus software or something similar if your pc does not turn off in safe mode that means you have virus or conflict between one software and another, or power the pc and press f2 or f12 or f1 it depends on your pc what button that it is but when the menu comesup choose the option that says repair and let it run you might not even need new parts, hope this was helpeful.