If you're going to end up throwing a PCI-e card in it later, just remember that the amd64 graphics drivers can suck a bit. From what I've heard, DRI and 3D just don't happen. With x86 you've got the binary nVidia drivers and the open source ATI onesthat do that kind of crap
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Otherwise, it looks like that machien will run BSD pretty solidly.
When I got my new machine, the major problems I had were my SATAII DVD drive messing up (Works fine otherwise, but couldn't install from disc. FTP worked perfectly.) and the onboard gigabit NIC wasn't supported (Attansic L1). I just looked at the specifications, and the shuttle board uses a Marvell one, which is supported by the msk driver
Score.
Should be good to go
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