Apple Macintosh PowerBook 1400 - Manual (Page 89)

The computer makes an unusual sound at startup.
m If you hear four tones, start up the computer with the
Disk Tools disk that
came with your computer. If the computer does not start up, or if the hard
disk icon does not appear, the hard disk may need repair. Contact an
Apple-authorized service provider or call the Apple Assistance Center. If
the hard disk icon does appear, see Chapter 7.
m There may be a problem with the information stored in the area called
parameter RAM (PRAM) and nonvolatile RAM (NVRAM).
Resetting the PRAM and NVRAM erases the contents of your RAM disk,
if you have one. It also reverts the settings on most of your computer’s
control panels to their defaults (original, standard settings). You may want
to check the settings in your control panels for memory, networking, and
monitors, and any aspect of your work that seems affected after you reset
the PRAM and NVRAM.
Follow these steps to reset the PRAM and NVRAM:
1. Shut down your computer.
2. Make sure the Caps Lock key is not engaged.
3. Position the fingers of your left hand on these keys: Command (x),
Option, and R. Locate the P key, so you can find it quickly for step 4.
4. Press the Power key (marked with “on/off”) to turn on your computer.
Immediately after you hear the startup sound, press and hold down the
Command (x), Option, and R keys at the same time as you press and
hold down the P key.
5. When you hear the startup sound repeat twice, release the keys, then
immediately press and hold down the Shift key to start up with your
Extensions turned off. Release the Shift key when you see the message
“Extensions Disabled” during startup.
If you don’t see the “Extensions Disabled” message, wait until startup is
complete, then press and hold down the Shift key while you choose
Restart from the Special menu. Continue to hold down the Shift key
until the message appears.
89 Tips and Troubleshooting