If anyone needs a cheap but powerful LAN server, I would highly recommend AMD64 as of now. I just put together a machine for about $600 that blows the doors off my old Rambus machine that I paid $1200+ for 18 months ago.
Start small with a single channel (754 pin) Athlon 64 2800. Load FC2 x86_64 and see for yourself. I'm currently running DHCP, DNS, FTP, rsync, sendmail, cyrus-imap, SSHD, Army Ops dedicated server, Battlefield Vietnam dedicated server, TeamSpeak2 server and Folding@Home (to take up the extra 80% CPU time) with no trouble whatsoever. And... unlike my old system, I can do this all in GUI mode without any lag. It's pretty incredible. Linux and AMD has really opened the doors to what's possible.