raid 0/1/10+ (I don't want to manage this at the OS level, bios software raid should be fine).
1+ pcie 16x
1+ pcie 4x slot or 1 pci-x slot (I want to be able to comfortably add a true hardware raid card later)
1+ pci slot (or 5.1+ onboard surround (or both))
4+ sata 1/2 & 1 pata
decent linux supported onboard video. I'd love to have an intel chipset but I can't find any boards meeting the rest of my requirements running intel. I've seen some that are running xgi that would do but as understand it (articles on phoronix) xgi doesn't exactly provide the best support for their drivers (on linux).
basically I'm looking at replacing my existing system with a system I can upgrade for the next few years.
I'm not entirely sure there are any boards that meet all my requirements, in fact I'm pretty sure at this point what I'm looking for doesn't exist, in which case I'm willing to listen to alternative suggestions that are close.