4K Eyefinity XFire
I am thinking into going with 3 4K monitors for gaming, my questions is if XFire the R9 290X would be fine or should I go with 3 GPU's instead?
most people will advise against 4k for gaming, as they are still a new enough technology where the response time and input lag, not to mention the hardware required for it is just not worth it. but since you seem to have the money for it, instead of 3 290x's i would suggest 2 780ti's, BUT i only suggest this due to the diminishing returns of 3 cards.
The 780ti is also a faster card and holds up better in multi card configurations in terms of frame-time-variance, this is simply a nvidia thing, but remember, the card is also more expensive.
Almost no one will ever actually recommend 3 gpus, as especially with the 290x, you need some serious cooling in your case.
if you are willing to pay for 3 290x, that is my recommendation for the 2 nvidia cards
If you only want to pay for 2, 290x's then i'd say stick with that option
they support 60hz now, but yeah, not an overly viable way to go for gaming yet. seriously save your money and invest it in something like a car or your childrens schooling lol
1440p is a great alternative, but really you are wanting to build a super system that is going to cost you much more money than it is actually worth
apparently NVidia had a setup of triple 4k displays at the recent show. I think they used either 2, 3, or 4 of the 780Ti cards. do a youtube search. either LinusTechTips of NCIX.com had it.
edit: quad titans