Which processor runs better for Postgresql?

I have a client who is running Postgresql 7.4.x series database
(required to use 7.4.x). They are planning an upgrade to a new server.
They are insistent on Dell.

I have personal experience with AMD dual Opteron, but I have not seen
any benchmarks on Intel's dual core Xeon. I've seen in the past Dell and
not performed well as well as Xeon's HT issues.

Can anyone share what their experience has been with Intel's dual core
CPUs and/or Dell's new servers?

I am hoping the client is willing to wait for Dell to ship a AMD
Opeteron-based server.

Thanks.

Steve Poe