Oracle9i, RAC on linux - server hardware recommendation

Hi All
We have decided on the following setup for our database server

Oracle 9i + RAC
Redhat linux (AS)
Netapp filer (for shared storage).

Any ideas\suggestions??go for 64bit cpu?? btw,cost effectiveness is NOT a major fector-we look for 1.reliability 2.performance.

   Thanks

     Yossi Ben Haroosh
     System Administrator
     http://www.netwarkit.info