Why no ATI cards for SH4?

[fabos]

First off I am new here and still have a lot to learn. I don't see anyone running ATI cards with SH3/SH4. Is there an issue with these cards? My current system in an Intel quad core 2.66, Bad Axe 2 MB, 2 Gigs DDR2, and an Nvidia 6600 video card (left over from my previous 3.6 gig system). My current system runs SH3 OK with some lagging when looking through the periscope in the middle of large convoys. I want to upgrade my video card before getting SH4 and was looking at the ATI 1950 series cards. If this a mistake and I should stay with the nvidia family for this game please let me know. The main reason I was going to go with the ATI card is that Corssfire looks to be bore flexible than SLI with respect to which products you link. I would like to get a second 1950 card in a few months as prices drop and link them. I an trying to keep my video card purchase price right around 200.00. What will be the best fit for my requirements.

Thx
Ron