R600 supports up to 4 cards in Crossfire
 

ATI is working on making the R600 capable of cooperating with up to 4 cards, quite a bit of GPU processing power if they get it up and running:

"The power supply manufacturers are thrilled about four cards in a high-end machine as such a system will demand a lot of power, probably even more than 1000W.

http://www.theinquirer.net/default.aspx?article=37484

This brings up an interesting point. Will Intel allow users to "SLI" their own cards, and what would they call it? ;)

AFR sounds like the way to go, especially if each card could get it's own frame to render. Not regulating all of the increased traffic through the PCIe lanes & chipset ought to help a fair bit as well.

Things just never cease to get more and more interesting I guess... :)

going from 16x to 32x for SLI didn't do much; maybe with Quad SLI it might give a difference... most single GPU solutions are still more than happy with 8x PCIe and since 99% of the gamers out there use ONE VGA card, let's not fall for any marketing b*llsh*t ;)

I thought that since the 8800GTX was greater than the power of two 7900GTXs that it was somewhat limited by only an x8 connection? I'd be interested to know either way, but my impression is that it was. If so, then R600 definitely would be as well.

2k watt psu?

Average household wall socket in the US = 110v x 15amp = 1650watts, a label will have to be added to make sure users are not powering their 2kw PC from a regular socket :)

Oh well, some are 110 x 20 amp = 2,200 w

Imagine the CPU required to not be CPU limited too with a Quad Crossfire setup! That should only help the power requirments... :-p

I think with Crysis running at 1600x1200 and higher at high AA levels with max detail, you'll be GPU limited again ;)

Maybe so, but there is always Alan Wake... :)