COD4 Help Needed

What kind of graphics card do you have?

it may be unsupported.

Go here, and choose the game you want to check if you can run it normally.sh4yo

you can defenatley install it your self, its really easy, if you can plug in a wall outlet you can install ur new Graphics card.

As far as selection, i would recomend an 8600 GT for good balance of price and power, i have ane and can run CoD4 just fine.