New Hard-Drive in Apple PowerBook G4
First, I'd like to say that my only experience with a hard-drive failure occurred while I was in the process of transferring my files to a new drive. I had a 40 GB drive in a Linux server, and on the drive I stored my entire music collection. At the time, my music collection amounted to about 20 GB of MP3 files; now, it's around 53 GB in size. The drive failed when I connected it to my new PC and attempted to start the machine; the old drive simply would not power on. I had to resort to a trick I had heard about from an IT guy at work: place the broken hard-drive in the freezer for 30 minutes and then retry. Sounds crazy, but I had honestly spent more than an hour trying to power on the drive with traditional methods. Sure enough, placing the drive in the freezer worked and I was able to transfer all of my files intact onto the new hard-drive. I had learned an important lesson: identify the data that's most important to you (large music collection, tax records, photos, etc) and back them up on a separate physical medium - preferably a CD or DVD.
Approximately a month ago, the hard-drive in our 12" PowerBook G4 began performing unreliably. The pattern it followed was that the machine would power on okay, but eventually the hard-drive would "stick" during an arbitrary task. All processes on the machine would be blocked until the hard-drive completed its task, which seemed to be endless unless I intervened by changing the orientation of the laptop. This looked pretty weird: me twisting and turning the PowerBook in the air as part of a desperate attempt to get the hard-drive to function correctly.
The diagnosis was not good: I needed a new hard-drive, stat.
The form-factor for laptop hard-drives is typically different from the form-factor of drives used in desktop computers. In the case of our 2004 12" PowerBook 1.33 GHz G4, it takes a 2.5" ATA-6 drive. To replace our ailing drive, I chose the Hitachi Travelstar HTS721010G9AT00. It's a 100 GB drive that operates at 7200 RPM, which is much faster than the 60 GB 4200 RPM drive that the PowerBook shipped with. This should make for faster application load times, which improves the overall performance of the system.
The installation of the drive required the disassembly of the PowerBook, which involved keeping track of many small screws, but didn't take more than an hour and was fairly straightforward thanks to instructions I found. Now, the hard-drive has been replaced, OS X has been re-installed, and my data has been restored. The drive performs great, and my PowerBook is once again in outstanding health!