Screen Blanking Nonsense
For some time I have noticed that despite configuring a screen saver timeout for 15 minutes, my monitor always blanked at exactly 10 minutes. Removing the xscreensaver, mate-screensaver, and mate-power-manager packages made no difference.
The problem did not occur in a console. Only when running X.
A little digging revealed that X is designed with a default screen blanking timeout of 10 minutes. The
xset q command will affirm that default.
For a few years now X has run on Linux systems without the need of an
xorg.conf file. A problem with that is the defaults all kick in. With some hindsight, I realized I never saw this problem for many years because I used a dedicated
xorg.conf. Little by little as I updated hardware and operating systems I slowly began not using the
xorg.conf file. Probably that is when I started noticing the fixed 10 minute blanking time.
The solution is to disable the X defaults. The Arch Linux wiki provides an example.
Section "Monitor" Identifier "LVDS0" Option "DPMS" “false" EndSection Section "ServerLayout" Identifier "ServerLayout0" Option "StandbyTime" “0" Option "SuspendTime" “0" Option "OffTime" “0" Option "BlankTime" “0" EndSection
Install the config file to something like
/etc/X11/xorg.conf.d/00-disable-dpms.conf. Just like that the X defaults are vaporized.
Dedicated screen saver apps should override these defaults. Curious they do not.