I experience the same thing on a Thinkpad T41 with a ATI Radeon 7500 M7. As soon as I enable MergedFB and attach a second display I experience occasional freezes. No need to invoke any xrand tool.
-- [dapper] xrandr freezes the system (radeon, MergedFB) https://launchpad.net/bugs/47775 -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
