Comment Exactly what IBM did, but IBM did it easy. (Score 1) 94
IBM's T221 monitor, the now ancient 3840x2400 22" 200dpi display, did the exact same thing.
It had 4 DVI inputs (newer models can support 2 dual-link DVIs), splitting up the screen into 1-4 stripes, depending on your bandwidth and setup. It's also directly plug & play, with no setup issues whatsoever on Linux, for what it's worth, and max frame rate is simply bound to how large each link is offering.
I've got a single card driving 2 T221s at a whopping 12Hz (single-link DVI each), and some low-res 30" 2560x1600 monitor with the displayport connector. 22 megapixels from 1 card is pretty nice, and I could be driving the T221s at 24Hz if I had the dual-link DVI connectors.
They were very flexible in their setup, not sure what Asus did here to make it a pain to set up.