Asus has come out with a Dual GPU version of the 760. The branded it the Mars. What do you think of the chances of seeing a R9 290x Mars edition once aftermarket coolers are allowed.
I'd like to make a guess, but I can't really. I'm surprised to see as low a card as the 760 getting the dual treatment ahead of the 770 and 780, but maybe that's a licensing issue. Given the heat issues with the R9 290x, you'd need a massive heatsink to cool two of them.
If I had to, I'd say a dual R9 290. But that's just a guess.
I think a dual 780/ti would be insane as they are already really expensive, two of them would cost an absolute fortune, whereas a OCd dual R9-290 (using decently binned chips) could reasonably be expected to be priced around that of the 780TI. However they would probably run closer to the 300W of the 290x when overclocked than the 250W of 290, that is 600W per card! What an absoloute monster, two of these would be 1.2K W!
The 290x is to expensive relative to performance, it wouldnt make much sense doing a dual 290x (300USD extra a card for a few FPS)