Quote Originally Posted by JustinLovesIzzy View Post
my card isnt overheating, running at 40 degrees.
Your CPU is overheating, not your GPU. If it's not that, then it could be your PSU is at the end of its rope. It could either be your power supply doesn't have enough wattage to handle your GPU under load, or it's dying and not putting out enough power.

CPU overheating usually causes it/the driver to crash and reset, causing the screen to go black for a few seconds. It doesn't generally shut your PC down. CPU overheating, however definitely will cause a shutdown- it's a failsafe to prevent damage.