I suspect the "11 minutes" minimum is coming from your system->preferences->screensaver being set to 11 minutes; the figure reported in the gnome power manager dialog seems to be offset by the screensaver amount (even though it doesn't seem to be implemented like that); I've reported a separate bug about this disparity between the UI and what actually happens:
For now the best work around I can find is to set the gnome power manager display off timeout to be sufficiently large that the difference between that timeout and the screensaver timeout is the power off time that I actually want.
I suspect the "11 minutes" minimum is coming from your system- >preferences- >screensaver being set to 11 minutes; the figure reported in the gnome power manager dialog seems to be offset by the screensaver amount (even though it doesn't seem to be implemented like that); I've reported a separate bug about this disparity between the UI and what actually happens:
https:/ /bugs.launchpad .net/ubuntu/ +source/ gnome-power- manager/ +bug/190537
For now the best work around I can find is to set the gnome power manager display off timeout to be sufficiently large that the difference between that timeout and the screensaver timeout is the power off time that I actually want.
Ewen