What with the price of older-but-decent video cards and monitors being very reasonable, I decided to move from the dual-head display I have been using in various forms for the past 15 years to triple-head. I was currently running dual-head using a single vNidia 9800GT card and two monitors. I added a second vNidia 9800GT and a third Samsung SyncMaster 930b 17" monitor which was attached to the new video card.
After some aggravation, I got it working, except that the Google-Chrome browser goes wonky in the display, but Firefox and other apps seem to be unaffected. If you want to see the wonky behavior, a video is available. As it was, it was mostly unusable for daily work and completely useless for games.
After much tweaking and swearing, I chose the path of least resistance and purchased a newer video card that would work out-of-the-box with three monitors, a 4GB nVidia GeForce GTX 1050 Ti.
There's a lot of help with this setup when using MS Windows as well as special external hardware that accomplishes it. For Linux, it was necessary to get a single head working with the nVidia driver, then use nvidia-settings to configure all three heads. Also. many of these multi-monitor setups used for gaming are used with wide-screen displays. That seems a little excessive to me, but that may be in my future if I have the extra cash.
As a result, the display performs flawlessly across three heads, but I need to learn the widescreen tweaks for my older video games. I can do that with information from the PC Gaming Wiki, an excellent site for the underlying details of PC games.
UPDATE - Nov. 26, 2017
I just acquired an Ultra-Wide-Screen monitor, an LG 20UM57-P. Resolution is 2560x1080 @60-Hz. It's different than viewing three separate monitors and may take some getting used to.