Are you happy with the x1800xt? I don't know what the deal is but my new computer which has the 1800 runs about the same as my old agp ati9800 pro. I can't figure out whats going on with it. I play eq2 and see basically no upgrade in performance. I have 2gigs ram and p4 3.2 ht and a asus p5ld2 deluxe mobo and can't run game any better than my old computer with 1/2 the ram a 2.6 p4 and a agp 9800 pro.
i thought that it had to be the same type of card? like, 1800xt with another 1800xt, x850 with another x850 and so on. the only difference with nvidia sli is that sli requires an identical card, ie. same type, same brand, same amount of memory. whereas crossfire is flexible enough to allow a board of a different brand, different amounts of memory etc, as long as its the same chip. or something like that.
my two cents.. well at least thats as much as i understand.