[Bug 30153] IBM X31 freeze under X, shortly after boot

[Olivier Cortes]

Public bug report changed:
https://launchpad.net/malone/bugs/30153

Comment:
I've reinstalled the machine from scratch (breezy + dist-upgrade to dapper). It still freezes under X with linux-686.
  * first time i was playing with gdesklets, freezed 30 minutes after login ;
  * second time it freezed @ gdm login (didn't have the time to type anything).

I did a memtest, one complete pass, no errors reported (ran 54min).

i booted 2 times the 2.6.15 386 kernel, and the machine doesn't seem to freeze with it. it ran all day long without freezing and i halted the machine. Now it has been running for 2 hours without any problem, and the machine is quite stressed (importing repeatedly my music library in banshee and rhythmbox).
I will let it on this night to see if the 386 is the solution or not.

In case it matters, the following list of apps is installed on the
system (my personnal additions to ubuntu) :

http://deep-ocean.net/files/karmak-desktop.txt

when the machine freezed, I tried Alt-SysRq-R then Control-Alt-F1, but
it didn't work (i tried when the machine was alive and it worked, a
keyboard mapping problem is out of cause).

What can I do to dig more ? is there any kind of "debug mode" in the
kernel ? An auto-core-dump feature which could be done without SysRq ?

Informations of the machine :
http://deep-ocean.net/files/x31/  (dmidecode, dmesg, lspci-vv)

I can provide any info on the machine, even a ssh access. I dedicated it
to finding the cause of this freeze : if i cannot resolve this issue,
dapper is no use for me...

Please give me any advice... Thanks in advance.