The flat-panel iMac’s friendly form masks a computer that can be devilishly difficult—but not impossible—to upgrade. Although you risk damaging your iMac if you perform the following procedures incorrectly, taking those risks can bring rich rewards, such as maximizing your iMac’s internal RAM without having to pay Apple a $200 premium for additional RAM (and installation). In addition, you don’t have to pay a technician to upgrade your iMac’s hard drive (and your iMac will be up and running far more quickly).
Upgrading the internal RAM and hard drive is a complicated process. These upgrades will void your warranty, and if you perform them, you’ll leave clear evidence that you’ve opened your iMac. If you’re not comfortable rummaging around inside a computer, don’t upgrade your iMac beyond installing an AirPort card and additional RAM in the user-upgradable area of the iMac.
Now that you’ve been suitably warned, turn off your iMac and take the following steps to upgrade its RAM and hard drive.
What You’ll Need:
Project Difficulty: Hard
Step 1: Make the Mac Comfy
Retrieve the box your iMac came in and remove the Styrofoam piece that secured the iMac’s base and screen. Place the rounded portion of the Styrofoam on a work surface with the open slot facing you. Detach all the iMac’s cables except the power cable. While supporting the iMac’s neck and base, lay the iMac on its back so that the arm and screen lay atop the Styrofoam and the Apple logo on the front of the iMac faces right. You may want to place a towel beneath the iMac base to protect your work surface and the base.
If you’ve disposed of the original packaging, construct a protective cradle for the iMac’s display out of stacks of books and a towel.
Step 2: Access the User-Upgradable Components
Using a #0 Phillips screwdriver, loosen the four screws at the bottom of the user-access plate. These screws remain attached to the plate, so once they’re loose, pull on two of them to remove it. Set it aside.
Beneath the cover is the AirPort card slot (A) and one user-upgradable RAM slot (B) . Before proceeding, touch the inner metal plate to discharge any static electricity you may harbor; then unplug the iMac’s power cord.
(If you intend to upgrade the iMac’s internal RAM and hard drive, don’t upgrade the RAM and AirPort card yet. The RAM and AirPort slots should be empty when you access the interior of your Mac. If they’re occupied, remove the RAM and AirPort card, and then replace them when you’ve completed the internal upgrades.)
The user-upgradable RAM slot accommodates a 128MB, 256MB, or 512MB PC133 SDRAM 144-pin SO-DIMM. To upgrade the RAM, insert a compatible RAM module at a 45-degree angle and press it into place. To add an AirPort card, slide the card in so that the AirPort label faces down, and attach the AirPort antenna.
These iMacs can hold as much as 1GB of RAM, but the default amount of RAM in new iMacs is only 256MB. Because you can’t purchase 768MB of RAM on a single module, it’s impossible to upgrade the iMac’s RAM to its full capacity via the user-upgradable RAM slot unless you have 512MB of RAM in the internal RAM slot. The following steps will show you how to upgrade an iMac’s internal RAM.
Step 3: Remove the Bottom Housing
Using a #15 Torx screwdriver, remove the four Torx screws from the bottom of the metal housing (C) .
Place your fingernails in the plastic seam that runs around the bottom of the iMac’s base, and gently pull down so that the bottom housing opens toward your work surface (D) . Put a phone book underneath the housing to support the edge closest to you (you could damage the cabling inside the iMac if you force the bottom housing to lay flat).
To detach the bottom housing from the upper base, you’ll have to disconnect six cables: the rectangular power connector (E) , the hard-drive and optical-drive data connector F, the AC-line filter connector (G) , the AirPort-antenna connector (H) , the video connector and its cover (I) , and, once you remove the Torx-10 screw, the grounding cable (J) . Pay attention to how these cables are arranged so you can put them back properly.