Follow-Up: How to improve db performance with $7K?

Thanks for everyone's feedback on to best improve our Postgresql
database for the animal hospital. I re-read the PostgreSQL 8.0
Performance Checklist just to keep focused.

We purchased (2) 4 x 146GB 10,000rpm SCSI U320 SCA drive arrays ($2600)
and (1) Sun W2100z dual AMD64 workstation with 4GB RAM ($2500). We did
not need a rack-mount server, so I though Sun's workstation would do
fine. I'll double the RAM. Hopefully, this should out-perform our dual
2.8 Xeon with 4GB of RAM.

Now, we need to purchase a good U320 RAID card now. Any suggestions for
those  which run well under Linux?

These two drive arrays main purpose is for our database. For those
messed with drive arrays before, how would you slice-up the drive array?
Will database performance be effected how our RAID10 is configured? Any
suggestions?

Thanks.

Steve Poe