Over time, the cooler wears out. Especially the ball bearing of the fan is susceptible to wear and tear or can get stuck. A broken radiator can be recognized by a loud rattling or you can't hear anything that indicates a jammed fan. If the cooling fails completely, the laptop turns itself off after a while to prevent overheating. If the cooler is defective, don't hesitate and replace it as soon as possible, as the mainboard and the entire notebook can suffer enormous damage due to overheating.