Ace's Hardware has put together a fairly comprehensive comparison
between Xeon & Opteron platforms running server apps. Unfortunately,
only MySQL "data mining" benchmarks as the review crew doesn't have that
much experience with OLTP-type systems but I'm gonna try to convince
them to add the ODSL DB benchmarks assuming they work fairly well with
Postgres.
Read up the goodies here:
http://www.aceshardware.com/read.jsp?id=60000275