RHELv4 and v5 - So slow as to be unusable. (Solved)

[Gary E Barnes]

The symptoms were that anywhere from 10 minutes to 10 hours after 
rebooting a RHELv4 or RHELv5 machine (one that previous ran RHELv3 with no 
problems) would get "slow".  Where "slow" means anything up to 30 seconds 
to respond to any command typed that has not just previously executed and 
a reboot/halt/shutdown would never complete (not even overnight).  Other 
symptoms were that the system clock would seemingly "stop"---what actually 
was happening is that time moved forward for several seconds, then 
suddenly would jump backwards several seconds at once.

The problem was something in the BIOS.  Flashing the affected machines 
with a newer version of the BIOS fixes the problem.

To anyone with IBM ThinkCentre 8187 machines, if your BIOS isn't the 
latest (2005) version then upgrading would be a good idea if you ever 
intend to run Linux on those boxes.
We have eight of those machines.  The two running the oldest version 
(2003) would not run RHELv4 properly.  Others with the 2004 and 2005 
versions were OK.

Thank you everyone for your suggestions.  This time it wasn't NFS (usually 
is), or NTP (sometimes), or even I/O handling (rare).  It was the 
"hardware".

        Gary