Dapper complete system freeze---could be 'ati' driver or epiphany browser

[Sean Hammond]

I have a terrible bug with ubuntu dapper that I'm getting desperate to solve.

The machine in my office completely freezes every now and then (maybe
every day or two). The screen freezes, mousepointer freezes,
ctrl-alt-backspace doesn't work, I can't go to another virtual
terminal, nothing. I have to kill the machine with the power switch.

My bug report:

https://launchpad.net/distros/ubuntu/+bug/50687

is getting no attention, and I can no longer put up with the situation
as I keep losing work. I feel this must be a bug that others are
experiencing, it must be reported elsewhere, or there must be
SOMETHING I can do to debug this problem a litte and make a more
effective bug report or find help. But I don't know what to do, so I
need help.

I suspect it might be due to the ati graphics driver. I'm using the
opensource driver called 'ati'. It might also be to do with the
epiphany web browser, as I feel that epiphany is always open when the
freeze occurs. I haven't noticed any other pattern to it.

Here is lshw for my machine:

https://wiki.ubuntu.com/SeanHammond?action=AttachFile&do=get&target=marley-lshw.html

and xorg.conf is at the bottom of this email.

Can anyone point me to a bug report that might be relevant, or suggest
something I can do that might tell me something about the problem?

This sort of thing isn't supposed to happen on Linux!

# /etc/X11/xorg.conf (xorg X Window System server configuration file)
#
# This file was generated by dexconf, the Debian X Configuration tool, using
# values from the debconf database.
#
# Edit this file with caution, and see the /etc/X11/xorg.conf manual page.
# (Type "man /etc/X11/xorg.conf" at the shell prompt.)
#
# This file is automatically updated on xserver-xorg package upgrades *only*
# if it has not been modified since the last upgrade of the xserver-xorg
# package.
#
# If you have edited this file but would like it to be automatically updated
# again, run the following command:
# sudo dpkg-reconfigure -phigh xserver-xorg

Section "Files"
 FontPath "/usr/share/X11/fonts/misc"
 FontPath "/usr/share/X11/fonts/cyrillic"
 FontPath "/usr/share/X11/fonts/100dpi/:unscaled"
 FontPath "/usr/share/X11/fonts/75dpi/:unscaled"
 FontPath "/usr/share/X11/fonts/Type1"
 FontPath "/usr/share/X11/fonts/CID"
 FontPath "/usr/share/X11/fonts/100dpi"
 FontPath "/usr/share/X11/fonts/75dpi"
        # paths to defoma fonts
 FontPath "/var/lib/defoma/x-ttcidfont-conf.d/dirs/TrueType"
 FontPath "/var/lib/defoma/x-ttcidfont-conf.d/dirs/CID"
EndSection

Section "Module"
 Load "GLcore"
 Load "bitmap"
 Load "ddc"
 Load "dri"
 Load "extmod"
 Load "freetype"
 Load "glx"
 Load "int10"
 Load "type1"
 Load "vbe"
EndSection

Section "InputDevice"
 Identifier "Generic Keyboard"
 Driver "kbd"
 Option "CoreKeyboard"
 Option "XkbRules" "xorg"
 Option "XkbModel" "pc105"
 Option "XkbLayout" "gb"
EndSection

Section "InputDevice"
 Identifier "Configured Mouse"
 Driver "mouse"
 Option "CorePointer"
 Option "Device" "/dev/input/mice"
 Option "Protocol" "ImPS/2"
 Option "Emulate3Buttons" "true"
 Option "ZAxisMapping" "4 5"
EndSection

Section "Device"
 Identifier "ATI Technologies, Inc. Radeon 7500 (RV200 QW)"
 Driver "ati"
 BusID "PCI:1:0:0"
EndSection

Section "Monitor"
 Identifier "HP L1740"
 Option "DPMS"
EndSection

Section "Screen"
 Identifier "Default Screen"
 Device "ATI Technologies, Inc. Radeon 7500 (RV200 QW)"
 Monitor "HP L1740"
 DefaultDepth 24
 SubSection "Display"
  Depth 1
  Modes "1280x1024" "1024x768" "800x600" "640x480"
 EndSubSection
 SubSection "Display"
  Depth 4
  Modes "1280x1024" "1024x768" "800x600" "640x480"
 EndSubSection
 SubSection "Display"
  Depth 8
  Modes "1280x1024" "1024x768" "800x600" "640x480"
 EndSubSection
 SubSection "Display"
  Depth 15
  Modes "1280x1024" "1024x768" "800x600" "640x480"
 EndSubSection
 SubSection "Display"
  Depth 16
  Modes "1280x1024" "1024x768" "800x600" "640x480"
 EndSubSection
 SubSection "Display"
  Depth 24
  Modes "1280x1024" "1024x768" "800x600" "640x480"
 EndSubSection
EndSection

Section "ServerLayout"
 Identifier "Default Layout"
 Screen "Default Screen"
 InputDevice "Generic Keyboard"
 InputDevice "Configured Mouse"
EndSection

Section "DRI"
 Mode 0666
EndSection

-- 
https://wiki.ubuntu.com/SeanHammond