Acer XB323UGX User Manual page 23

Adjusting the Brightness
Open the Brightness control and select the brightness setting using the Navi/
OK button. When you are done, press the Navi/OK button to exit.
Selecting the Input
Open the Input control and select an available input source. When you are
done, press the Navi/OK button to go back one level.
EN-13