Apple Macintosh PowerBook 145B - Manual (Page 34)

m Hold down the power button for 5 seconds.
When you let go, the computer turns itself off. Turning the
computer off with the power button erases the contents of a
RAM disk.
m Restart from a floppy disk.
1. Insert the Disk Tools disk into the floppy disk drive.
2. Press the power button.
If the computer turns on, there may be a problem with your
hard disk. You may be able to fix the problem yourself (using
the Disk First Aid program or another disk repair program;
see the chapter on disks in the reference section). Or you can
take the computer to your authorized Apple service provider.
18 Chapter 1: Setting Up Your Macintosh PowerBook