I love building new machines. I just pieced together this gem on Newegg and I can't wait to get started on it! I went with AMD over Intel as compared to the i5, the Phenom II 965 is marginally better for music applications and costs a little less. Plus I needed a motherboard with firewire, and I found a really great cheap one specifically for the AMDs, while finding an Intel one was a bit more effort and $. Firewire is essential for me as my MOTU recording unit is firewire only.
EDIT: I wound up going with Windows 7. I'm not looking for gaming power, I just want a rig that won't get crushed by Reaper or Sonar while recording. I need processing power more than RAM. This rig is pretty powerful and should last me a long time. Heck, I'm still using my old AMD Athlon 64 3000 I built back in 2004! I recorded two home albums all with only 1 MB of memory on that thing
Anyway, here's what I bought. $675 shipped!
Expect some new instrumental music from me later this year
FW800 on that board? Does it support SLI cards?
And stop being cheap, double that RAM order at once.