This could be a problem with some 3D screensavers taking down your machine. It is probably nothing wrong with gnome-screensaver itself, but your video drivers. What kind of hardware (esp. graphic card) do you have? Can you go through the screensavers manually, and see if you can find the one that kills the machine? Does it help to specify "Blank screen" in Screensaver Preferences?
** Changed in: gnome-screensaver (Ubuntu) Status: Unconfirmed => Needs Info -- gnome-screensaver causes my laptop to hang on resume from memory-suspend https://launchpad.net/bugs/58963 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs