Just purchased a 60hz 4k Monitor and a 1300W Gold PSU, my board supports SLI wondering what the best option is to push that monitor? I would also consider AMD or waiting for newer models of gfx chipsets.
I would wait. I get the feeling that even 780ti sli is a struggle @ 4k. Its payable, but playing that much and not getting high/very high on most games is disappointing. SLI 880 may help with that problem. And to answer your first question: 290x CF>780ti 3gb>780 6 gb SLI.