suspend - When Power Manager isn't handling something, what handles it? - Ask Ubuntu

i'm running xubuntu 16.04 lts 64-bit, general question.

in power manager, there's checkbox "handle display power management". handles display power management when box unchecked?

additionally, determines how system behaves if uncheck power manager startup list? determines happens if power or sleep buttons pressed, if battery low, or if system idle long amount of time?

xubuntu uses xfce desktop environment default. power manger more xfce application called xfce4-power. can read official documentation of specific preference app in here: http://docs.xfce.org/xfce/xfce4-power-manager/preferences#display

if checked "handle display power management" box, deal below 3 display options.

check handle display power management allow power manager manage laptop's display.

the 3 options — blank after, put sleep after , switch off after — theoretically in ascending order of power saving potential. however, not laptop hardware capable of making distinction among these 3 modes , there no direct indication on laptop if display being turned off, suspended or blanked. may have experiment see which, if any, of these options yields power savings.

power manager assume each of these options work @ hardware level , attempts prevent illogical configuration; e.g., blank after period greater put sleep after one. in setup 1 shown in screenshot above, if drag on battery put sleep after slider down to, say, 5 minutes, blank after slider automatically move 1 minute less. likewise, if try reduce switch off after period less other two, move other 2 sliders 1 minute , 2 minutes less, respectively.