Everytime i run a game my screen shuts off

Hello, i looked for solutions in another threads, but is always the same answer "new cpu", or "a new fan", but... what's my problem? well... everytime i run a game my screen shuts off (probably my computer) and i gotta restart my PC, so, i can't play anything. I already checked my pc temerature, but is around 20-22 when that happens, so, the fan is not a good answer.

Thanks.