If your motherboard has a built in display adapter,then try running your system without the 760 and run Furmark,see if you can find the same figure in HWmonitor.This way you can judge if its your GPU or not.If the GPU is not the problem,then try unplugging the CPU cooler and reinstall it properly.
Else if the GPU is the problem,then RMA it stating the issue.If you don't have a warranty anymore,send it for servicing to your dealer.Hope this helps.