Why am I not able to adjust the brightness setting on my Acer Chromebox?
You can adjust the display brightness setting for the CXI3 Chromebox using the brightness control keys on your Chrome keyboard as shown in the image below.* If you are using a standard PC keyboard, you can use the F6 and F7 keys to adjust the brightness.
Note: You will not be able to adjust the display brightness using the Chrome OS settings menu. The menu will show a brightness control slider, but you will be unable to adjust this setting.*
* This feature may vary depending on the monitor model you have connected.