random crashes after installing X with nvidia

[hendrik@topoi.pooq.com]

I finally got X up with the nvidia drivers!  Lovely screen.  I had no 
idea my monitor was capable of such high resolution.  It's now my 
favorite machine to work on.  Despite the crashes.

Every now and then it just stope, and becomes completely unresponsive to 
mouse and keyboard input, and ignores attempts to ssh in from another 
box.  Hardware-level reset is the only way to recover.  Not too painful, 
because of he reiser file system, but definitely disturbing.

Before X, it just never crashed, and has been runnin as a NFS file 
server to the other machines on the LAN.

The nvidia kernel I use is

nvidia-kernel-2.6.12-1-amd64-generic_1.0.8756-1_amd64.deb

with

nvidia-glx_1.0.8756-1_amd64.deb

The kernel is vmlinuz-2.6.12-1-amd64-generic
obtained from Len Sorensen's site (did I remember the spelling of his 
name correctly?

Once, only once, when it crashed I still had a functioning keyboard -- 
enough to ctrl-alt-F1 to a root console, where I saw a flurry of 
messates about eth0 -- complaining about not haveing access to it 
and wondering whether another device might be competing for interrupts.

I'd like to get this fixed.

Is this a known problem and I should upgrade kernel and driver?
Is it likely to be hardware (which would be awkward because the warranty 
on the assembled bor is from a company that, although it supported 
Linux, is now defunct.
What diagnostic information should I be collecting?
Are there any other very maintenance actions (in the words of Dave Barry 
:))? 

-- hendrik