Hardware advice for scalable warehouse db

Hi list,

My employer will be donated a NetApp FAS 3040 SAN [1] and we want to run
our warehouse DB on it. The pg9.0 DB currently comprises ~1.5TB of
tables, 200GB of indexes, and grows ~5%/month. The DB is not update
critical, but undergoes larger read and insert operations frequently.

My employer is a university with little funds and we have to find a
cheap way to scale for the next 3 years, so the SAN seems a good chance
to us. We are now looking for the remaining server parts to maximize DB
performance with costs <= $4000. I digged out the following
configuration with the discount we receive from Dell:

1 x Intel Xeon X5670, 6C, 2.93GHz, 12M Cache
16 GB (4x4GB) Low Volt DDR3 1066Mhz
PERC H700 SAS RAID controller
4 x 300 GB 10k SAS 6Gbps 2.5" in RAID 10

I was thinking to put the WAL and the indexes on the local disks, and
the rest on the SAN. If funds allow, we might downgrade the disks to
SATA and add a 50 GB SATA SSD for the WAL (SAS/SATA mixup not possible).

Any comments on the configuration? Any experiences with iSCSI vs. Fibre
Channel for SANs and PostgreSQL? If the SAN setup sucks, do you see a
cheap alternative how to connect as many as 16 x 2TB disks as DAS?

Thanks so much!

Best,
Chris

[1]: http://www.b2net.co.uk/netapp/fas3000.pdf