Hello all,
I wish we rpi2 with ubuntu mate it worked that way:
At the time when I do not use RPI, lcd monitor turn off.
When the mouse will move the monitor to go on.
Currently, thanks to xscreensaver it works that way, but I have a question because xscreensaver do not turn off (power off) the monitor only to it black, please help.
Hi,
take a look here but I don’t know if the same rules apply to Raspi?:
I tried this but with no positive result
What are your power options settings like?. Do you have it set to suspend or hibernate?. 
Quick Power-off in Blank Only Mode
If the display mode is set to Blank Screen Only and this is checked, then the monitor will be powered off immediately upon blanking, regardless of the other power-management settings. In this way, the power management idle-timers can be completely disabled, but the screen will be powered off when black. (This might be preferable on laptops.)
I would like to take this option but unfortunately it does not work in xscreensaver:(
Add\edit /boot/config.txt
hdmi_drive=1
hdmi_blanking=1
It works!
Furthermore, have a look in the “/boot/config.txt” documentation on more options.
If you have an HDMI monitor plugged with sound output, and want to have sound enabled, you may choose the option “hdmi_drive=2”. Otherwise, the “hdmi_blanking=1” is the right option to put the HDMI monditor in standby mode (screen switched off after a while).