Video Card Problems

Two weeks ago I purchased a Radeon 9600 XT 128mb video card. I have been having a lot of problems with my fps with all the special effects off like shadows and all that stuff and my fps will be any from 3-100. I never had this problem when i had my nvidia 64 mb which isnt nearly as good as this card. I dont think I should be having any problems with this card. If anyone thinks they can help me please do because I really want too be able to use the simulator with best graphics and no fps problems. Thankyou so much.

i think that you need to still configure the card first.