Hardware for a database server

Hi List!

I have to purchase new hardware for my company's new dedicated PG
database server. As it is my first time shopping for this special
purpose, I would feel less nervous if I could get some knowledgeable
feedback on this matter.

What is it for?

Short version:
It is for a medium sized database. ~ 50 users, < 5GB, biggest table < 1
million tupples, 60 tables, lots of indices, triggers, rules, and other
objects.

Long version:
The server is going to run Debian with PG 7.4.x. and will be a
dedicated database server.
The database is going to hold data on upcoming events for print in a
weekly magazine and for various websites fed by it (Falter in Vienna,
Austria - if u wonder). The websites will be fed by slave db's on other
machines (mySQL or PG as well, replicating relevant data from the
master daily or several times a day), so there wont be too much load on
the master from that. The server in question will serve the web-
frontends for data-input mainly. Apache and php will be used.

There will be about 50 users hacking in data but hardly ever more than
25 at a time. 5-10 normally.

The Database holds about 60 tables and 150 indices. Lots of views,
triggers and rules. I expect the largest table to grow by 20.000 rows
per week and never get above 1 million rows. The size of the database
will strongly depend on whether we include blobs or store them
separately, which has not been decided yet. If we don't inline the
blobs, I don't expect the database to grow over 5 GB, less than 1 GB in
the beginning. Blobs will use several times that. All in all I would
not call it a large database. There will be several smaller databases
on the same server, but all of them together not as big as the first
one. And we expect the thing to grow, but not so as to spend more money
on hardware right now.

What will I purchase?

CPU:
Single AMD Opteron.
Opteron, because i plan to migrate to amd64 debian as soon as Debian
has a stable release.
Single, because multi-CPU would only make sense if the CPU could ever
get the bottleneck. But I don't have to fear that, right? No need for a
dual-cpu setup?
Should I consider Athlon 64 FX or Athlon 64? I guess socket 940 has
more future than socket 754, right?

Motherboard:
?? According to CPU, Raid controller and 2 NIC integrated maybe? ..

Controller / Hard Discs:
RAID 5 with 4+ discs including a hot spare. But SCSI or SATA?
I am undecided on this. Until about a year ago, I would have said SCSI,
period. But I have read of SATA RAIDs for entry-level-servers doing
quite well and Linux dealing with it ever more smoothly. ([1], [2])
So I wonder if it is still a good decission to spend 3 times the money
per gigabyte on SCSI?
And do 3ware Controllers still have the best driver support under
Linux?
Any harddisks known to be especially apt for databases (hi I/O load
..)?

Power supply:
Secured with UPS, auto-shutdown before power fails, so do I need my
RAID controller battery-backed still?

RAM:
As much as the motherboard will bear. 4 GB probably. This seems the
easyest point to decide on. Correct? DDR SDRAM PC333 or PC400?

Other:
2 NICs, ??

I appreciate any comments, hints or corrections.

Regards
Erwin Brandstetter

[1] http://www6.tomshardware.com/storage/20031114/index.html
[2] http://www.linuxmafia.com/faq/Hardware/sata.html