PowerEdge 2650 freezing up

[Joshua Colvin]

Hi all,

We have a PowerEdge 2650 with RHEL ES 4.0 U4, kernel 2.6.9-22.0.1.ELsmp,
which has frozen-up 3 times in the past month. The first time was
Nov 21, then second 2 days ago, and again today. "Freezing-up" means
you cannot ping it, ssh into it, and if you are ssh into it your
session is frozen. The only thing I've been able to do is reboot
and add more monitoring. I can't find a pattern; ps, netstat, nfsstat,
vmstat all report normal values of operation, /var/log/messages shows
nothing out of the ordinary, and the box is not even under a heavy load.
Because of this I'm suspecting a HW issue, maybe failing power 
supply, a short or bad RAM. I'm not familiar with the 2650, but
whenever I've had HW issues on PowerEdge 1850's, Dell always outputs a 
message in /var/log/messages. I am wondering if anyone knows of
ways I can test the HW-side of things, to start ruling things out?

I am trying to set this up:
http://kbase.redhat.com/faq/FAQ_80_4154.shtm
however since I inherited the system and am unfamiliar with DRAC it's
not yet set up. 

Thanks for any tips,
Josh