The only difference is that some video cards will directly support "9" where as if the card is "8", software support is required for "9". A little performance boost with the card directly supporting "9".
I recently got a computer Dell 3000 with a 3 gHz P4 processor and 512 MB ram, upgraded soundblaster 5.1 24 bit sound card. Unfortunately, only an integrated video card and only 1 available PCI slot. Apparently there are PCI video cards such as an ATI 9200 128MB card. It says it has DirectX 8.1 graphics support. However, I notice some games say they need DirectX9.0 (which comes with the computer - I checked). Is this a problem? Thanks in advance...

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