Problem with computer game instalation, even though my computer surpes the requirements?

i bought madden '07 (for $10) recently at best buy, and when i got my game i put it in my computer and started the downloading process after puting the serial id number in the box that asks for it, it gives me a blank doent that has agree or disagree on it, and it is not still loading by the way, so for the sake of moving on, i click agree and then a error message pops up saying you need directx version 9.0c or greater to run this program, so i go to the direct x website and download the latest direct x version. after rebooting my computer, i tried downloading it again, and the same message appears, i meet all the requirements (on the box, and i even did the diag check to make sure that it was not bad and the diag test said i had direct x 9.0c, and had the check next to it saying it is ok, and had checks next to all the other things too) my computer was built for gaming and it handles battlefield 2, which i play frequently, nicely and battlefield 2 has much higher requirements