Hardware Upgrade Plans

I am planning out the addition of a DB server to sit beside the current box. No real need to move until later on this year - what technologies should I be on the lookout for?

AMD planning a new socket for Opteron level processors? My current box runs dual 246's and I'd want to run dual dual or quad processors for the new one. SATA vs SCSI? SAS? What’s the best for database servers. DB reaching 1GB+ ranges.

I plan on building it and testing it out with Fedora Core 5 (or the latest version) ... that should be up to date with PHP and MySQL.

I also plan on just swapping the boxes temporarily while taking the current box and reformatting it and upgrade to all the latest software and then return it to run a separate Web and DB server.

I expect my usage to possibly double, with a large spike around the beginning of 2007.

Any thoughts? AMD doesn't seem to be too talkative about their plans for the next gen socket for servers - mostly desktop level stuff.