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  • Lubuntu 12.04, XP dual boot
  • ATI RS480 graphics

Problem I get random lockups about once every 3 hours or so.


  • PC hangs with (typically) a small bar-code style square in top left quadrant of the screen or else a totally white screen.
  • nothing entered at the keyboard causes any response (ALT SYSREQ b etc)
  • power off/on is necessary to get going again
  • has happened with both Firefox and Chromium, so can't blame the browser
  • cannot ping or ssh to the PC from another device on the same LAN when it happens
  • nothing is output on Netconsole (on the same LAN) at the moment of the lockup
  • XP never locks up so it can't be bad memory
share|improve this question
Check .xsession-errors in your home directory, /var/log/Xorg.0.log, /var/log/syslog, /var/log/dmesg for errors. Try SYSREQ S to sync disks before power cycle. – jippie May 29 '12 at 20:09
I can't see anything in those log files that looks significant. Syslog : theres nothing around the time of the latest crash. Dmesg : assuming the timestamp is the number of seconds since boot, then theres nothing there either.Xorg : this has no timestamp at all, but none of the messages in there look relevant. – user67009 May 31 '12 at 18:14

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