I managed to create an apport report just before screen freeze (changing console to ctrl+alt+f1) and saved to file this time. See attached report.
** Attachment added: "Apport report" https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1389732/+attachment/4399452/+files/apport.xorg.ks87z0ff.apport -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xorg in Ubuntu. https://bugs.launchpad.net/bugs/1389732 Title: The computer freeze randomly To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1389732/+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