when my pc cools down it wont boot
This statement leads me to think that you may have a contact problem with one of your daughter boards
(one of the circuit boards that plugs into the motherboard)
Metal expands under heat and shrinks with cooling over time this can cause oxidation even on gold, this oxidation could be causing your problem.
If it were my system, I would remove each daughter board, one at a time, lightly
clean the contacts on both sides of the board with a pencil eraser, then reseat that board where it came from, and then do the same with the next daughter board.