As far as I understand it has time racing condition between intel and radeon modules. And it may be related with vgaswitcheroo too. On earlyer versions of ubuntu changing the waiting time and the gfx mode in grub seemed to affect the bug somehow. Some combination of that even maked it disappear :)
-- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xserver-xorg-video-ati in Ubuntu. https://bugs.launchpad.net/bugs/727620 Title: [Radeon HD 5650 and 5470] Kernel BUG during recovery boot and in normal boot (Hybrid graphics) To manage notifications about this bug go to: https://bugs.launchpad.net/linux/+bug/727620/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp