Dell Alienware M14x (Early 2011) - Manual (Page 39)

CHAPTER 2: GETTING TO KNOW YOUR LAPTOP
37
F5 — Decrease display brightness
Press to decrease the brightness of the display.
F6 — Eject
Press to eject the disc from the optical drive.
F7 — Mute sound playback
Press to mute or unmute the sound.
F8 — Decrease volume
Press to decrease the volume level.
F9 — Increase volume
Press to increase the volume level.
F10 — Rewind or play previous track
Press to rewind or play previous track.
F11 — Play or pause
Press to play or pause a track.