I cannot reproduce this on current quantal with a radeon hd 5500 and xserver-xorg-video-ati 1:6.99.99~git20120913.8637f772-0ubuntu1, can you try upgrading please?
** Changed in: xserver-xorg-video-ati (Ubuntu) Status: New => Incomplete -- 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/1052031 Title: Xorg crashed with SIGABRT in OsReleaseSIGIO() To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-ati/+bug/1052031/+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