Whenever I run games on my PC the screen flickers with black blade like lines then my PC crashes and shuts down. I didn't always do this. It's a recent problem. I ran all virus scans and nothing! It only happens when I run a PC/DVD game. Also when I run this type of game my DVD drive disappears from the "MY Computer" screen. When I reboot the PC  the DVD drive returns. It's wierd.

 

My graphics card is an ATI Graphics 256 X800 UHMGA11. The sadest part of my problem is that my PC is still under tech warranty and I don't even want to get on the phone with an overseas tech for 5 hours! The last time I had a problem the phone call went on for two days! Honestly we had to finish troubleshooting the following day. It's sad! I appreciate any help that anyone can provide. Thanks in advance.

 

Bruce