HP Compaq Presario,Presario 800AP Supplementary Manual page 35

Tip
You can also adjust the
display brightness by
pressing Fn+F7 to decrease
the brightness or Fn+F8 to
increase the brightness.
Did you know...
Key combinations such as the
example Fn+F7 used above
mean that you should press
and hold down the Fn key,
press the F7 key, and then
release both keys
simultaneously.
If your display is too faint or too bright, the brightness controls
may not be set properly. To correct this condition, complete the
following steps:
1. On the taskbar, click Start, point to Settings, and then click
Control Panel.
2. Double-click Display and click the Settings tab.
3. Click the Advanced button to open the
RAGE MOBILITY AGP Properties dialog box.
4. Click the Color tab. Under Brightness, click and drag the
Desktop slider to the desired brightness.
5. Click OK to close the dialog box and click OK again
to close the Display Properties dialog box, then close the
Control Panel window.