I go System preferences->Energy Saver-> set a time of 15 min to turn off the display. This works for few days but them it stops working and monitor does not turn off. WHen I return to my machine in the AM, I find the monitor still on, and has been on all night. I never know when this setting will stop working. I have to select a different time in the Settings or restart the machine to have it work properly again.
How can I fix this?
MDIJB