i just installed call of duty 4 modern warfare and when i try to play it a window pops up and says: video card or driver doesn't support UBYTE4N vertex data. is there a way to fix this cost free, cuz every time i get a little problem customer service has to run a stupid $30 diagnostics even tho i tell them exactly whats wrong.

i know it has to do with my video or graphics card, and please dont tell me i need a new one!

i have a inspiron b120 with windows xp.