Quake 4 error

I download a demo of quake 4 and after i boot it up error has ocured have to shut game down(but not only on quake i also get the same thing when viewing movies on the net but not all the time.

Spec
amd 64 3000+
1.5bg ram
fx5900 xt 128mb

 

Your graphics chipset is not supported by quake 4(or at least its not listed). As for the movies crashing, update your graphics card drivers, your media player and your web browser. Quake might run after you've updated the drivers but I doubt it. If it does it'll look and play like sh*t.