Instead of running four 1080p monitors, I use a curved 55" Samsung 4k TV. It is the equivalent of four 27" 1080p monitors.
It's easy to snap windows to corners and sides with Windows 10. And, no bezels getting in the way.
TVhttps://www.amazon.com/Samsung-UN55JS9000-Curved-55-Inch-Ultra/dp/B00TS76VOK/(There is a newer model available)
Video CardI run an Nvidia Titan X, but this is newer, better and cheaper:
https://www.amazon.com/EVGA-GeForce-FOUNDERS-Support-11G-P4-6390-KR/dp/B06XH2P8DD/ref=sr_1_1?ie=UTF8&qid=1493523448&sr=8-1&keywords=nvidia+gtx+1080ti(You can get away with a lesser card, but I recommend something with 6GB video ram to push the 4k)
ConnectionHDMI 2.0 (60fps at 3840 x 2160)
Considerations*55" may be too big. You may want a 47", which is the equivalent of four 23" 1080p monitors. Go to a TV store and stand 2-3 feet away from each. Find your personal preference.
*Make sure your TV has a "game mode" or "dot-by-dot" mode. It'll be buried in the menus somewhere. This is the only way to get a sharp image. Remember this when you hook it up for the first time. It looks like crap until you sort this setting.
*This setup works great for photo/video editing, and projects that require multi-tasking. I regularly have Excel, Chrome, Word and Ultraedit open in each corner. It's a time-saver.
*Gamers may not like the 60fps bandwidth limit of HDMI 2.0. For everything else, you'll never notice.