[LinuxBIOS] Board recommendations?

Guys,

I'm looking for two different boards on which LinuxBIOS is known to work
well (perhaps it'll end up being the same board).  I need 1+ gigE on these
that has open drivers in Linux.

Board 1a (for deployment on actual scientists' desks):
  One socket Operton/Athlon64
  PCIe x16 for single nVidia graphics card

Board 1b
  Like 1a, but two Opteron sockets

Board 2a (for RAID disk nodes in cluster):
  Two socket Opteron
  HTX slot             \ usable simultaneously
  qty 2 PCIe x8 slots  /

Board 2b (supposing there's no PCIe+HTX option):
  Two socket Opteron
  qty 3 PCIe x8 slots  (2 raid cards, 1 PCIe Infiniband)

Can anybody offer any recommendations for any subset of those?  For the
Board-1 options, it'd be handy if somebody could vouch that they've managed
to bring up an nVidia PCIe card successfully.

Thanks, y'all,

-mcq