Storage is a requirement for everybody, but one problem that constantly arises for geeks is running out of hard drive space.  We go from small 20 MB hard drives to 200 MB, up to 2 GB, then 20 GB, then 200 GB and beyond.  Eventually, computers will have holographic hard drives with terabytes and terabytes of data in them.

Until that happens, I’m content with upgrading a reasonable amount for what the storage trends say I should have right now.  My iMac shipped with an 80 GB hard drive (the lowest size — it’s the lowest in its class for processor and graphics card, the smallest screen size, etc.), and for a while I’ve been feeling constrained by this.  In December, I ordered a new 250 GB hard drive that was dead on arrival, so I had to ship it back and wait for a new one.  Well, I’m happy to announce that my hard drive finally arrived (and worked), so I did the switch, and I can now show everyone the process.  This will be a tutorial for replacing the drive on a 17”, pre-iSight iMac G5 only.  The 20” pre-iSight iMac and the iMacs with iSights, both G5 and Intel Core Duo, have different internal configurations and take different steps.

Note: If you plan to follow this tutorial, please read the entire article before you start.  I am not responsible for your data loss if you follow my directions improperly, or hell, even if you follow them correctly and they don’t work for you.

1. The first step, of course, is to buy a hard drive. You’ll need to assess your storage needs and financial capabilities, making a decision based on how much space you need, how much you can afford, and other factors like large partitions or drive speed.

   I chose a 250 GB, 7200 RPM Hitachi Deskstar as my new storage brick.  I chose this drive because it fared well against other drives in its class in benchmarks conducted by hardCOREware.net, and it had a good price of $83 at PC Parts Ohio.  (This doesn’t count the $6 initial shipping, or $27 to ship the dead drive back to them.) Your needs may vary anywhere from a 160 GB, 5400 RPM drive (not recommended for iMacs with drives greater than 80 GB) to a 500 GB, 10,000 RPM Raptor.  But whatever you decide on, you’ll need to order it, of course.

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   The next step is to transfer your data somehow.  There are about as many ways to do this as there are geeks replacing hard drives.  I chose to use a USB 2-to-SATA adaptor because I could partition and format the drive, transfer all my data at once, and have an exact duplicate ready to go immediately.  If you don’t choose to go this route, you can buy an external enclosure for the drive, allowing you to hook it up via Firewire or USB 2 (depending on the enclosure, of course).  Both of these techniques can be reused with other drives, in case you need to deal with internal hard drives for doing tech support, or if you want to replace your drive later.  Other backup solutions include using a dedicated external hard drive or some sort of removable medium, such as tape drives, DVD-R discs, CD-R discs, or (heaven forbid!) Zip disks or floppies.

   

   If you choose a transfer solution that allows you to mount the hard drive on your desktop (as in, the adaptor I’m using, or an external drive or enclosure), you can mirror your current internal hard drive on the new one to get an exact copy.  This will ensure that everything is copied exactly from your old drive to the new ones; do not simply drag folders over, because there are hidden directories that OS X relies on that you will not transfer, and your drive will not be bootable.  Use Disk Utility’s Recover option or a utility like Carbon Copy Cloner to create an exact duplicate of your data.  Make sure you use something that makes the drive bootable, or you may have to do it all over again.  It will take a long time to complete, so give it plenty of time.  And try not to do much while this is going on, because changes you make may not be mirrored.

   If you choose to use removable media (that are smaller than your current internal drive — you can get tape drives in very large sizes), you’ll need to back up everything you want to keep to enough disks to hold all of it, then do the installation and reinstall the system.  Don’t bother backing up the /System directory, and leave the /Library directory if you’re absolutely certain that it does not contain anything you want to keep or can’t install again. Additionally, if you plan to reinstall all your applications, you can leave the /Applications folder.  What you shouldn’t leave are the /Users folder and any folders you may have added to the vanilla OS X installation such as Classic, the Developer Tools, or other data folders (I have folders called Documents, Games and Downloads at the root of my drive, for example).

   Once you’re done backing up and are absolutely certain that everything you want to keep will be available, you’re ready for the actual switch.

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   Click image for The Big Picture

   Unplug everything from the back of your iMac and set it on a smooth, flat surface.  I recommend against working on your computer on carpet because you could build up static electricity, and you could lose screws more easily.  Open the iMac by unscrewing the three lossless screws in the speaker area.  Take the back off and set it where it won’t be stepped on or gather dust or lint. You can take the opportunity to blow out some of the dust that may have accumulated inside the iMac, especially near the processor assembly.

4. Now you’ll need to remove the hard drive.  Take off the plastic piece that partially covers the drive (be careful not to lose any screws during this process!).  Set it aside, and remove the three screws that keep the hard drive mount in place.  Disconnect the power and SATA cables on the left of the drive (if the drive is at the top — if it’s at the bottom, these will be on the right) and the tiny cable on the opposite side, and pull out the drive.

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   Now you need to remove the drive mount, which is the piece of metal attached to the drive with 4 TORX screws.  Take these out and put the new drive into the mount, replacing the TORX screws.



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   Now, do everything you did in reverse.  Be sure the small rubber inserts surrounding the screws in the drive mount stay in place; these act as shock absorbers for the drive.  These screws can also be tricky to get into the right spot, so you may need a magnetic screwdriver, needlenose pliers or tweezers to hold them in place.  Make sure you reconnect all three cables that you disconnected earlier, and replace the plastic piece. Align the back cover and screw it back in.



7. So now that you’ve got your new hard drive in your iMac, you can reconnect the cables and turn it on.  If you mirrored your old drive directly to the new one over USB and SATA or an empty external enclosure, you can simply boot the machine and it will start up exactly as it did before.  (If you don’t see the gray Apple logo when you boot, you did something wrong.  Retrace your steps and see if you made a mistake; if you can’t find the problem, leave a comment or contact an authorized repair center.) If you used an external hard drive to store the data, you’ll need to boot from it or from a CD before you can mirror your data to the new drive.  If you used removable media, you’ll need to do a fresh install of OS X before you can start transferring your data back.  I’ll leave it as an exercise to the reader to figure out how to correctly migrate his data from the media to the correct locations. You can then reinstall any applications you may not have saved.

And that’s it!  I certainly hope this tutorial helped someone out there, and that I didn’t just write it for nothing.  I know I certainly had fun replacing the hard drive in my iMac, at least when I got to the actual removal, and I’m sure you will too.