I have installed a brand new 12.04 on my Dell XPS M1330 laptop. Initially, it is able to reboot/shutdown normally. However, after I installed my first software, ubuntu-tweak, my laptop was frozen in the reboot/shutdown process consistently, result in a black screen.
Because of my suspicion, I remove and purge ubuntu-tweak, then try again. It worked this time! It is obvious that ubuntu-tweak cause this power manager problem on my laptop.
However, I have encountered another reboot/shutdown freeze after I started to install most of popular programs in the Ubuntu Software Center. I have been force logout during the installation. After that, my laptop have the reboot/shutdown freeze constantly!
I am wondering what kind of bug would cause this problem and how to resolve it. Any idea?