Apple PowerBook (3400 series) - Manual (Page 110)

The monitor goes dark after a few minutes.
Screen dimming may be turned on. Move the pointer to restore the screen’s
brightness. You can change the interval before screen dimming takes effect in
the PowerBook control panel.
The computer freezes when screen dimming takes effect.
Screen dimming does not work with some programs. Contact the program’s
manufacturer to see if there is a newer version of the program that is
compatible with dimming. If the problem persists, you can open the
PowerBook control panel and turn off screen dimming.
There is wavy or jittery interference on the external monitor.
This interference may be generated by a magnetic field. If the monitor is near
another piece of equipment (such as a TV, speakers, or another monitor),
move the monitor away from the equipment.
You connected a different external monitor and it turns on but doesn’t display an image.
Once you set the resolution for an external monitor, any other external
monitor subsequently connected to your PowerBook will attempt to use that
resolution. If you cannot set a resolution for the new external monitor that
results in an image on the screen, you may need to detach the second monitor,
discard the Display Preferences file (in the Preferences folder inside the
System Folder), reconnect that monitor, and choose a resolution over again to
see a satisfactory image. For instructions, see the Monitors topic area of
Mac OS Guide, available in the Guide (h) menu.)
Printers
The computer can’t find the printer.
m Make sure the printer is connected and turned on.
IMPORTANT Make sure that all equipment is turned off before connecting or
disconnecting cables.
m The printer may not be selected in the Chooser. Open the Chooser and
select the printer you want to use. If the printer is connected to a port,
make sure the correct port is selected.
110 Chapter 7