I have the sam issue and I have the server in another house.. I need to restart it again, last message in kern.log is about the nic;
Nov 2 16:57:29 evo kernel: [ 11.854112] type=1505 audit(1257177449.426:11): operation="profile_replace" pid=716 name=/usr/sbin/tcpdump
Nov 2 16:57:31 evo kernel: [ 13.816151] e100: eth0 NIC Link is Up 100 Mbps Full Duplex
Nov 2 16:57:31 evo kernel: [ 13.816289] ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
Nov 2 16:57:32 evo kernel: [ 15.377338] type=1503 audit(1257177452.951:12): operation="open" pid=847 parent=846 profile="/usr/sbin/mysqld" requested_mask="r::" denied_mask="r::" fsuid=0 ouid=0 name="/sys/devices/system/cpu/"
Nov 2 16:57:33 evo kernel: [ 16.153567] type=1503 audit(1257177453.726:13): operation="open" pid=918 parent=917 profile="/usr/sbin/mysqld" requested_mask="r::" denied_mask="r::" fsuid=0 ouid=0 name="/sys/devices/system/cpu/"
Nov 2 16:57:35 evo kernel: [ 17.538557] type=1503 audit(1257177455.110:14): operation="open" pid=1114 parent=933 profile="/usr/sbin/mysqld" requested_mask="r::" denied_mask="r::" fsuid=0 ouid=0 name="/sys/devices/system/cpu/"
Nov 2 16:57:35 evo kernel: [ 17.726787] type=1503 audit(1257177455.877:15): operation="open" pid=1121 parent=1120 profile="/usr/sbin/mysqld" requested_mask="r::" denied_mask="r::" fsuid=0 ouid=0 name="/sys/devices/system/cpu/"
Nov 2 16:57:36 evo kernel: [ 18.817482] type=1503 audit(1257177456.969:16): operation="open" pid=1141 parent=1140 profile="/usr/sbin/mysqld" requested_mask="r::" denied_mask="r::" fsuid=0 ouid=0 name="/sys/devices/system/cpu/"
Nov 2 16:57:37 evo kernel: [ 18.878522] type=1503 audit(1257177457.029:17): operation="open" pid=1152 parent=1151 profile="/usr/sbin/mysqld" requested_mask="r::" denied_mask="r::" fsuid=0 ouid=0 name="/sys/devices/system/cpu/"
Nov 2 16:57:42 evo kernel: [ 24.652044] eth0: no IPv6 routers present
Have never looked in the kern.log before so I have no idea if theese massages are new or common.
I also have some kind o fpentium and 512meg mem, the machine has never failed before, I upgraded it today.
[edit] this is a pure server, no screen, only ssh-access, so I would not blame the graphics drivers.[/edit]
[edit possible fix]
Added apm=off nomodeset to the boot options, my grub.lst now looks like this:
title Ubuntu 9.10, kernel 2.6.31-14-generic-pae
root (hd0,0)
kernel /boot/vmlinuz-2.6.31-14-generic-pae root=UUID=0943496f-8c97-4f59-a2c0-4b5fd64e3c40 ro quiet splash apm=off nomodeset
initrd /boot/initrd.img-2.6.31-14-generic-pae
quiet
And I now have 15 minutes uptime as opposed to max 10 before the change. It apparently has something to do with monitor sleep and as I have no monitor some shit hits the fan. I hope the server keeps on running now (16 minutes :)).
There's a bug filed: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/474930
That would be my five cents (18 minutes!).
[/edit possible fix]