I have been experiencing this problem for quite some time now, but I
have found that when I use gentoo-sources-2.6.20-r4 instead of other
kernels, the problem seems to go away.

Last night, I was trying 2.6.21-r2 to see if I still experienced the
problem.  I had started a lengthy copy process before going to bed. 
When I woke this morning, the computer was in fact locked up.  Like
always, the cursor still moved around the screen when I moved the mouse,
but button clicks and keyboard keystrokes had no effect.  Again, I had
to use the Magic SysRq sequence to reboot the machine.  When it had
rebooted, back to 2.6.20-r4, I restarted rsync to finish the copy
process.  To my surprise, the copy was already finished.

I should point out that every time I experience this, I try
unsuccessfully to ssh into my computer.  The computer does not respond
to any network traffic I initiate, SSH, ICMP, HTTP, etc.

I have an nVidia GeForce 6600 running the proprietary "nvidia" driver. 
I h ave no DPMS option in my xorg.conf, and xscreensaver is running,
though set to never display a screen saver.

Dustin C. Hatch
http://www.dchweb.com



Peter Humphrey wrote:
> On Friday 08 June 2007 10:19:08 Sebastian Redl wrote:
>   
>> Michael Ulm wrote:
>>     
>>> In xorg.conf, in the monitor section, I was missing the line
>>> Options="DPMS"
>>>
>>> I'll still have to research how leaving out this option could lead to
>>> crashes, so I appreciate any insight this group may give.
>>>       
>> Since practically every monitor supports this, and since it's
>> practically always enabled, it may be that other code paths of X.org are
>> insufficiently tested, causing the server to crash when it wants to put
>> the monitor into a power saver mode. That's my best guess.
>>     
>
> My experience doesn't match this. I've had to remove the DPMS option from my 
> xorg.conf to prevent lockups. Those only happened if I left the KDM login 
> screen up until the screen blanker cut in, but then the only way out was a 
> hard reset.
>
> Apart from wanting my machine to do only what I tell it to, and I'm quite 
> capable of switching my monitor off when I'm not using it, I think it's 
> dangerous for any system to make assumptions about what facilities will be 
> required in any particular case.
>
> My hardware is an nVidia GeForce 7300 GS driving an Iiyama AU4831D screen, 
> and the X nv driver comes from x11-base/xorg-x11-7.2. Or sometimes I play 
> with the nVidia closed-source drivers, but as far as I know that doesn't 
> affect the lockups.
>
>