I played some games on PC and suddenly my whole display went grey (striped) and I couldn't do anything. After I restarted my PC, I didn't see the startup or windows logo or anything...after a while my whole monitor was purple, then there were random colours. My monitor works perfectly fine, but the problem may be in my graphics card. Any help ?
Cpu, gpu, motherboard, ram, psu? If you have onboard video, try using that. If you don't have any way to test the gpu in another computer, or another gpu in your computer, it's going to be difficult to troubleshoot.