Serverwork chipset are great, Tyan has this mobo
Thunder 2500 that kicks butt. It has AGP pro support and everything you want in a mobo...if you can afford it.
If your don't mind waiting, in one or two month, you should be able to get dual Athlon solution, but no one knows how well it will perform, but a dual 1.2 Athlon system will kick everything out there if there is no compatibility problems.
If you wanna save some money, there are lots of Via based mobo now out there from MSI, Tyan, Abit, Epox..., but you may see some incompatibility problems. You may have to load new bios, patches and other stuff to get the system run correctly, but if you know how to deal with computer, you should be able to get those system up and running without much trouble.