Way back when Crossfire first came out, I remember 2 things being said about it:
1) You could use non-identical cards, so you could buy a high end one now, but another high end one 6 months down the line, and crossfire link them. This was one of the ways ATI claimed it was superior to SLi.
2) Unlike SLi, where 2 'standard' cards could be SLi'd, you had to specifically shell out for a crossfire 'master' card, which cost considerably more than the bog standard version of the same spec, to be able to run a crossfire setup.
Now, i've just been hunting around on Scan and the like for Crossfire Master cards, mainly for the 3xxx series just to see what the price difference *was*, as I wasn't expecting any 4xxx ones to be out yet. But I can't find anything. Did ATI/AMD remove the need for a master card, and like SLi you just buy 2 normal cards and link them together now?
Also, does anyone know anything about Crossfire, and what is and isn't a good board for it? I've noticed that all of the P35 Crossfire boards (what few there are) only have 1 x16 PCI-E slot, with the other actually being a x4, which would cripple your second graphics card. It looks like you have to go up to X38 to get a 'proper' crossfire board with 2 x16 slots (something like the Asus Maximum Formula, as I want to remain with DDR2 for the time being - http://tinyurl.com/6bqdeu ) but I have little idea how this stacks up. Reviews are suggesting it's good, but, well, I trust the opinions of a lot of the people on this forum more than reviewers I don't know ;) For reference, I was looking at the Abit IP35 Pro XE ( http://tinyurl.com/4erwsj ) before I started thinking I might want a Crossfire setup in the future if I went with ATI/AMD for the graphics card.