I just completed an order of 100 small form factor units by Shuttle with Ubuntu
installed on them. I know they work. I put AMD on all of them. I load a flat 1gb
of ram and install 80GB drives. Ubuntu recognized everything. Of course, I'm
partial to Shuttle but others of course work.

Its not a matter of what works with this or that distro but what "just" works.
Unless its highly proprietary hardware - it will most likely work.