So here's the thing. To get full 4K HD play at 60 Frames a second it going to take a lot of GPU horsepower today. Figure the top end video cards for today. I'd look at one 980 Nvidia or Titan per display.
Also, you only get 30Hz over HDMI 1.4x so you have to know your HDMI ports, cards and connections.
Most folk are sticking with 1080p until the GPUs catch up and come down in price but if you are going to do this, you are looking at a few thousand buck upgrade.
Need expert advice - I want to upgrade from two old 19" (4:3) and one 22" (wide) monitors to a pair of 32" 4K UHD TV's. My work is proprietary software plus I will have at least 9 up to 15 or so browser (Chrome) sites open at any one time. Desktop is Core i7 950 with 16G RAM & 2 1.5 TB HD with 2 Nvidia GeForce 9500 GT graphics cards & W7 Pro. I know I would need to have HDMI 2.0 from card (s?) and to TV's. A good cost-efficient card? These will be on desk with about a 2.5' viewing distance. No gaming involved but some video editing. I need the real estate so I won't be minimizing/maximizing as much as I do now plus I need it to be big enough for these old eyes to read. I would sincerely appreciate any advice.

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