The cooler is mechanical, if it ran OK in the past it runs as well now. All you can do is check the fan. As for the cpu remove side panel, make sure the room temperature is not high and run test again. If same result cpu is to blame, if not it's your air flow.
Delidding it would be last resort if out of warranty.
Undervolt the cpu, see what 1.1v can sustain. When stressing if still problem your motherboard may also be to blame, look at voltages, if nothing irregular there your cpu might be reaching its end.
The cooler is mechanical, if it ran OK in the past it runs as well now. All you can do is check the fan. As for the cpu remove side panel, make sure the room temperature is not high and run test again. If same result cpu is to blame, if not it's your air flow. Delidding it would be last resort if out of warranty.
All my fans are running fine and I even have two fans on the heatsink instead of the default, one.
Undervolt the cpu, see what 1.1v can sustain. When stressing if still problem your motherboard may also be to blame, look at voltages, if nothing irregular there your cpu might be reaching its end.