Last couple days I have been getting screen freeze/lock ups before system reboots itself. After rebooting I get the message from windows saying system was shut down unexpectedly and that the problem seems to be with my nvidia tnt video card. Also says "display driver unable to complete a drawing operation, check manufacturer for update". Well, I did download the latest driver from nvidias website and it seemed fine for a day, now I am getting same message again. Can someone help ?