Switching UseFBDev to True solves the hang. I also needed to add:
Option "MonitorLayout" "TMDS" Option "PanelSize" "1680x1050" To get it to sync to my monitor correctly. -- On PPC64 update to 6.6.1 causes machine to hang https://launchpad.net/bugs/54352 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs