To use a special function key, press and hold down the Fn key, press the key with the desired image on it, and then release both keys.
See the following table for definitions of the special function keys.
Fn + F2 wireless network card (select models only): toggle on/off
Fn + F3 Sleep mode: toggle on/off
Fn + F4 display: toggle in the following order
notebook display (default)
external monitor (if connected)
both the notebook display and the external monitor (if an external monitor is connected)
Fn + F7 display: decrease brightness
Fn + F8 display: increase brightness
Fn + F9 CD/DVD: play/pause
Fn + F10 CD/DVD: stop
Fn + F11 CD/DVD: play previous track
Fn + F12 CD/DVD: play next track
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