Using Fn Hot Keys The combination of the Fn key plus another key creates a hot key —a shortcut key sequence—for various system controls. To use a hot key, press and hold Fn, press the appropriate second key, then release both keys. Table 1-6. Fn Hot Keys 1-8 Product Information HP Omnibook XE4100/XE4500 Hot Key Effect Fn+F1 Decreases the display brightness. Fn+F2 Increases the display brightness. Fn+F5 Toggles among the built-in display, an external display, and simultaneous display on both. Fn+F8 Toggles the built-in keypad on and off. Does not affect an external keyboard.
If Num Lock is on, then the numeric functions are active; otherwise, cursor control is active (as marked on an external keyboard). Fn+F12 Enters Hibernate mode. Fn+NumLock Toggles Scroll Lock on and off. Fn+Page Up Increases the audio volume and cancels the mute setting. Fn+Page Down Decreases the audio volume. Fn+Backspace Audio mute.