[CentOS] Fighting some install issues with a new box

Folks-

I have had a machine dropped in my lap that I am trying to get CentOS
4.1 to run on as a first pass (the hope is for it to eventually run
Rocks -- http://www.rocksclusters.org , which uses CentOS 4.x as its
underlying OS).

The machine has 2 Opteron 250DP (2.4GHz) with 4 GB of RAM. It is using a
Tyan Thunder K8WE (S2895A2NRF) motherboard with an nVidia nForce chipset
-- http://www.tyan.com/products/html/thunderk8we.html. It is configured
to boot from an SATA drive (80GB) and then use 3Ware 8506-8 card with
8x250GB SATA drives in a big raid 5 as a data store.

So, CentOS appears to recognize the nics and find the boot drive well
enough to go through a complete install. Now this is where things get
"interesting" .. the install process hung for a very long period of time
during the "installing grub" phase (this was a cd install, so no post or
anything, done off-line). It finally rebooted, but it just hangs at the
"GRUB Loading stage2..."

If I boot the machine using the 4.1 install cd in rescue mode, I can see
the filesystem (the OS is installed). /etc/grub.conf doesn't look
unreasonable. One oddball thing is that I cannot see the 3ware card at
all (doesn't show up in lspci output).

Any thoughts? Anyone set up a similar beastie?

Thanks.

Sean