What should I do if my PC freezes?

Question

Iron

Hello, I have encountered such a problem. My PC freezes in games (in all my games (Doorkickers 2, Ultimate chiken horse, cs go, mudrunner, watch dogs 2) with a sound that I can’t imagine, it plays instantly for a second or less, and was once in Windows through minute after exiting the game.It may not always freeze, it happens after an hour or 3, it may not freeze at all.The computer is new, assembled in the workshop, only the SSD on which windows and other programs are installed was taken from my laptop (the motherboard burned out and it also freezes.) The computer freezes somewhere closer to the critical value (on the screen).

Temp. during normal operation.