Motorola ML900 Operation Manual page 41

Key
Switches the display output to one of the following when an
external device is connected.
Upon booting the system with CRT:
NOTES:
Serves as the sleep button that you can define with Windows'
Power Management. (See the "Power Management" in
Chapter 3.)
Switches GPS function on and off.
2-8
Description
LCD
LCD & CRT
If the display mode is set to 256 colors or lower, or in DOS
mode, there will be only two modes for selecting: CRT only
and LCD & CRT.
This function only applies to Plug & Play CRT monitors.
CRT
Operating Your Computer