I would like to upgrade my monitor to one 4k and add two more later, but don't know what video card or cards to go with? Would one gtx 780 or two gtx 780 will be find. I am running an I5 4670k, 8gb 1600mhz memory, and ow gtx 770 2gb.
For 4k. You will need two 780s or even better, two 290Xs (290x's perform better in 4k than 780/ti's) Here is an article with game performance: http://www.guru3d.com/articles_pages/gtx_780_ti_sli_geforce_review,23.html
Or even better, get a 295X2 if you can/want, it'll do better than anything out at the moment for 4k gaming precisely. But as mentioned before, you WILL need 2 cards, one card will get you only 17-28 FPS in most games.
depends on what you plan on doing? If you just want normal desktop stuff then one should be fine. If you plan on doing gaming then yea def want to get two.
For 4k. You will need two 780s or even better, two 290Xs (290x's perform better in 4k than 780/ti's) Here is an article with game performance: http://www.guru3d.com/articles_pages/gtx_780_ti_sli_geforce_review,23.html
Or even better, get a 295X2 if you can/want, it'll do better than anything out at the moment for 4k gaming precisely. But as mentioned before, you WILL need 2 cards, one card will get you only 17-28 FPS in most games.
One 4k monitor is fine with something like dual GTX 780s, but if you want to use Nvidia surround with 3x4k monitors, you should get at least 2 TITAN blacks, 3 would be recommended.