Sounds like DPMS off time is enabled (the default for that is 40 minutes). 
Possibly usefule commands
xset -q
xset -dpms

You can also control DPMS settings in xorg.ocnf:
http://xorg.freedesktop.org/archive/X11R6.8.0/doc/xorg.conf.5.html#sect4

-- 
monitor goes to sleep when it shouldn't
https://bugs.launchpad.net/bugs/378435
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.

-- 
ubuntu-bugs mailing list
[email protected]
https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs

Reply via email to