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Problems turning on or starting up your computer

The computer is turned on but the screen is dark.

One of the following is probably the cause:

m You have a screen saver program that darkens the screen when the computer has not been used for

a certain period of time. 

Press a key or move the pointer to turn off the screen saver. (Screen saver programs interfere with
the computer’s power conservation feature, so you may want to remove the screen saver or keep it
turned off.)

m Your computer has gone to sleep due to inactivity. “Wake it up” by pressing the Power key (marked

with a π) on the keyboard.

m The screen’s brightness control (¤) is not adjusted properly.

Check the screen’s brightness control and turn it up if necessary.

m There is something wrong with the power supply to the computer. Turn the bass unit over and

check the recessed well on the underside. You should see a green status light. If the green status
light is not on, try plugging the computer into a different outlet.

Make sure that the flow of air around the bass unit is not blocked.

The computer makes an unusual sound at startup.

m If you hear four tones, try starting up the computer from the system software CD-ROM disc. For

instructions, see “Starting Up From the System Software CD-ROM Disc” in Chapter 13. If the hard
disk icon appears, you can probably repair the hard disk using the instructions in “Testing Your Hard
Disk” in Chapter 13. If the computer does not start up, or if the hard disk icon does not appear, the
hard disk may need professional repair. Contact an Apple-authorized service provider or call for
assistance (see the service and support information that came with your computer).

Solutions 

to Common

Problems

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