[Can not turn display off]

I just in installed Ubuntu 22.04 and planning to use the board as photo frame on cron job (script) during certain hours of the day.

This is how I did on my raspberry pi(, that fried recently after about 7 years of service)!

 

However, I can not turn off display.

Commands I used on RPI do not work. Tried all kinds of various methods to turn off display

- xset

- vcgencmd

- xscreensaver

- tvservice

- All of the above as my <username> as well as "sudo"

 

All of them either don't do anything or blanks the screen but does not turn it off.

For some of the above commands it complains regarding

- VCHI initialization failed

I tried various things including sudo as well as adding my username to the video group, etc.

Nothing works.

 

Any help is greatly appreciated before I decide to return the board.

 

Thank you.