Are there settings enabled that could push the hardware a little harder?
If not, please follow instructions below
Please run Furmark to test your GPU
Please check inside your case for any dust and remove them if there are.
Please make sure you are not overclocking anything, if you do revert back to stock while troubleshooting.
Please make sure your GPU is properly seated, if necessary reseat it.
Please note the temperatures of your GPU when idle and under load and post the temperatures.
Please check in your BIOS for the 3.3v, 5v and 12v values, note and post them.
Run Furmark to test your GPU. Furmark tutorial
Run Furmark for around 30 minutes
Your GPU temperatures will rise quickly while Furmark is running. Keep a keen eye on them and abort the test if temperatures rise too high