Hello

Having downloaded EB a few days ago i decided to try the campaign. However after a few minutes the game seem to go slower and then suddenly everything seem to lock up completly, then the screen goes black and i`m sent back to desktop. However i get a windows message saying "nv4_disp Screendriver" could not be found.
Also the desktop wallpaper has turned into odd colours and the screen is reduced to 640x480.

The custom battles work fine though.

What could be the problem?