1. screen freezes. 2. Screen corruption - blurry lines 3. screen refreshes and system can be used again. 4. ATI Catalyst Centre informs me there has been a crash and an error report will be sent. 5. Graphics are really slow (moving a window across the screen is done in jagged slow movements instead of one quick smooth motion for example). 6. We reboot to get the system back to normal state Please tell me how to fix this.