I am running an Nvidia GTX-750 to an LG 49 inch TV @ 3840 x 2160.
The GTX-750 only requires 300 watts and can drive 4 monitors.
The 49" tv is overkill. I put the control bar at the bottom so it does not hurt my neck. Above the control bar is the console view, and at the top is track view. The console view can show about 25 tracks and busses. I put the inspector and browser on a second 24" monitor.
I can see a bunch of stuff at once, but I tend to use only the bottom 2/3 of the display.
I use multiple machines on th LG tv because it has 4 hdmi inputs. I also use mouse without borders to eliminate multiple keyboards/ mice. I have had this system for about a year now.