Dell UltraSharp 38" 1600p Curved Monitor - Manual (Page 71)

Operating the monitor
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Menu Adjusts the settings of the OSD, such as, the
languages of the OSD, the amount of time the menu
remains on screen, and so on.
Language Sets the OSD display to one of the eight languages
(English, Spanish, French, German, Brazilian
Portuguese, Russian, Simplified Chinese, or
Japanese).
Transparency Select to change the menu transparency by moving
the joystick (min. 0/max. 100).
Timer Sets the length of time for the OSD to remain active
after your last operation with the joystick.
Move the joystick to adjust the slider in 1 second
increment, from 5 to 60 seconds.