faced the same problem with my dell latitude. sometimes the screen resumed fine after closing and opening. But it often failed to resume. (At such times, pressing the power off button and hitting enter will shut down the system).
Got it fixed by following the thread http://ubuntuforums.org/showthread.php?t=134319 Fix: replace /etc/acpi/lid.sh with the following code #!/bin/sh # turns the screen off on lid close & on on lid open grep -q closed /proc/acpi/button/lid/*/state if [ $? = 0 ] then /usr/sbin/vbetool dpms off else /usr/sbin/vbetool dpms on fi -- Notebooks freezes after closing lid or pressing some FN key combination https://launchpad.net/bugs/65027 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
