LinuxLookup.com: Multiple Monitors with X Mini Guide

“When you set out to acquire your monitors and video cards make
sure that they are Linux compatible. I have found that Nvidia
chipset graphics cards work quite nicely (GeForce Line) as they are
quite Linux friendly. They are also fairly inexpensive which is a
plus. If you wish to use ATI cards be sure to stay away from older
models as some of them tend not handle acceleration under X very
well. If you decide to go the dual-head route you cannot beat
Matrox. Mixing AGP and PCI cards doesn’t matter. You will see
why.

“If they are of the same chipset or use the same drivers you
will make your life a lot easier. You will need a monitor for each
card (or for each port on dual-head models). Again, having all of
your monitors the same will make the setup very easy. If you want
to run a X session on each monitor then you can use any SVGA
monitor you want since different resolutions will not
matter…”

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