Upgrade an iMac

You may have been an early adopter, the first in your sewing circle to own a tray-loading Bondi blue iMac or fruit-flavored wonder--or perhaps you held off until the arrival of the slot-loading fruit flavors or earth-toned ruby and sage models. But your computer now seems a little rickety. Your applications are begging for more RAM, and your hard drive is just about full to the brim.

But buying a new machine isn't your only option. An iMac may look hermetically sealed--and its insides truly are harder to access than a Power Mac's--but with some time, some patience, and a reasonable amount of money, you can turn your iMac into a more capable computer.

Though you can't easily replace an iMac's G3 processor, there are at least two other ways to improve your iMac: increasing the amount of RAM, and replacing the hard drive with a roomier one. If you have a Rev. A iMac, you can also supplement your computer's video RAM. We'll show you how to accomplish all three tasks. The first set of steps (1 through 6) applies to the tray-loading Bondi blue and fruit-flavored iMacs; the second set is for slot-loading fruit-flavored models and for every iMac since. If you're up for an even greater challenge, consider Sonnet Technologies' Harmoni, a $300 card that combines a processor upgrade with a FireWire port (800/786-6260, www.sonnettechnology.com ). Check with the company to determine compatibility.

You may void your warranty when you perform these tasks, and with any hardware upgrade, some risk is involved. There isn't much danger that you'll actually damage your machine while performing this how-to's steps, but more than one person on Macworld' s staff has had trouble upgrading an iMac. The warnings and tips provided here come from hard-won experience.

Contributing Editor CHRISTOPHER BREEN wrote the directions for tray-loading iMacs. Associate Editor JENNIFER BERGER and Associate Technical Analyst JASON COX wrote the directions for slot-loading iMacs.

What You'll Need

Here's a rundown of the supplies necessary to upgrade an iMac.

1. A 5,400-rpm ATA or Ultra ATA hard drive (faster drives may be too hot for iMacs).

2. Your Mac OS installation CD, for help in backing up the old hard drive and reinstalling the OS when you're finished upgrading.

3. New RAM. The first slot-loading iMacs accommodate up to 512MB of RAM; iMacs released in the summer of 2000 and later take a maximum of 1GB. Check out www.ramseeker.com for a list of RAM vendors and prices.

4. A way to back up your old hard drive's contents: an external CD-RW drive, a Zip drive, a hard drive, or a network backup solution. (See "Save Your Data," September 2001.)

5. Old-fashioned hardware: a magnetic Phillips screwdriver, to reduce the risk of your dropping screws into your iMac; a flathead screwdriver; and needle-nose pliers, helpful for grabbing and holding the tiny screws you'll find in your iMac.

6. A small box, to hold the removed screws so they don't roll away and to keep them easy to find.

7. A grounding strap, to keep your iMac safe from static electricity (they cost less than $1 at electronics and computer stores).

8. A soft surface, such as a pillow, blanket, or towel, to prevent scratches on the monitor or case.

9. One hour of your time (or less).

1: Tray-Loading iMacs


Prepare the iMac and Crack the Case Before you can expose the inside of your tray-loading iMac to the outside world, you must prepare it for the operation.

Even if you intend only to upgrade your iMac's RAM, something could go wrong, causing your data to go the way of the dodo. Back up your data to a network, the Internet (iDisk accounts are free at www.apple.com ), or external media such as Zip disks or CD-RWs.

Unplug any cables attached to your iMac, including USB, modem, Ethernet, audio, and power cables.

To access the innards of your early iMac, you must place it monitor-side down. Protect the monitor from scratches by placing the iMac on a soft surface, such as a pillow, blanket, or plush towel. If you use a pillow, make sure it's flat enough to prevent the iMac from rocking while you're working on it.

Turn your iMac so you can see its bottom (the white side). There you'll see a handle with a Phillips screw in the middle (A). Remove this screw, and put it where you won't lose it.

Retract the handle, and give it a gentle tug to remove the white plastic cover. Because the cover is secured in some places with plastic tabs, you'll hear an unsnapping sound. Don't worry--this sound is a normal part of the operation. Put the cover aside.

2: Venture inside the iMac During this stage, you'll protect your iMac from a shocking experience, dislodge a few cables, remove more screws, and extract the iMac's core from the case.

If you have a grounding strap, attach it to your wrist and the iMac's metal case to release static buildup. If you don't have one, touch the iMac's metal case to discharge static.

You'll see four cables attached to a rectangular metal box--two large clumps of multicolored wires and two gray cables (A).

Remove the round gray cable to the right, and use a Phillips screwdriver to loosen the two screws that keep the larger gray cable clamped to the case.

Remove the large multicolored cable by pressing down on the tab inside the metal cutout and pulling firmly on the connector. Then pull straight up on the smaller multicolored cable connector to disconnect it. Remove the small screw that holds the smaller multicolored cable in place.

Remove the two screws beneath the clear plastic handle near the top of the case (just beneath the serial-number sticker) (B).

The motherboard/drive assembly is ready to be extracted. Move the cables out of the way, and pull straight up on the plastic handle.

3: Upgrade the RAM These iMacs ship with a scant 32MB of RAM. You can add as much as 256MB of RAM (144-pin, PC100 SO-DIMM) to the RAM slot. As we went to press, RAM was inexpensive, priced at around $70 for a 256MB module.

Position the motherboard/drive assembly so that the CD-ROM drive is closest to you (A).

Near the top of the motherboard is a shiny metal cover. To access the iMac's spare RAM slot, remove this cover by prying the side of the cover open with a flathead screwdriver. The cover's edges are sharp! To avoid injury, don't touch the edges with your hands.

Beneath the cover, you'll spy a white plastic bracket (B). This is where the RAM goes.

When you're handling RAM, don't touch the gold-plated contacts. Keep the new RAM in its static-proof bag until you're ready to install it.

Remove the RAM module from its bag, line up the notches in the RAM module with those in the RAM slot, and press the RAM into the slot at a 45-degree angle until it's securely seated. Now press down on the top of the RAM module until it snaps into place.

If you have a Rev. A iMac, you'll see a similar empty RAM socket on the left side of the motherboard. This is the video RAM (VRAM) socket. While you're inside your iMac, it's not a bad idea to max out your iMac's VRAM by adding a 4MB SGRAM SO-DIMM (around $20).

4: Upgrade the Hard Drive The Bondi blue iMacs originally carried 4GB hard drives, and the five original fruit-flavored iMacs had 6GB drives. If your iMac is running low on storage space, this step is for you. Compatible ATA hard drives that hold as much as 60GB are now available for less than $300.

You must remove the CD-ROM drive to expose the hard drive beneath. The CD-ROM drive is held in place on the front of the drive mounting by a couple of hooks (A) that slip through slots in the drive cage. To remove the CD-ROM drive, push in the face of the drive to slip these hooks out of the slots, then lift the drive up and over the top of the cage. Once the CD-ROM drive is clear, disconnect its ribbon cable. Put the drive aside.

With the hard drive exposed, remove the metal clip over the drive and the two Phillips screws on the top of the cage--on the left and right sides of the drive (B). These screws secure the hard drive's bracket to the cage.

Pull the bracket from the cage, and disconnect the drive's data and power cables. Unscrew the bracket screws, remove the old drive, and set it aside.

With the new drive, reverse this process by attaching the bracket and cables, slipping the bracket back into the cage, screwing the bracket to the cage, reinstalling the clip over the drive, and replacing the CD-ROM drive.

5: Put It Back Together Putting Humpty-iMac back together again is largely a matter of following the preceding steps in reverse order. However, you should be aware of some places where the process isn't as simple as it may seem.

Before reinserting your iMac's motherboard, make sure that all connectors and chips are firmly seated.

Grasp the motherboard/drive assembly by the plastic handle, and slide it back into place. To do so, push the four cables aside, making sure they're clear of the assembly. You'll see metal pins on the side of the drive cage. These pins must slide behind the iMac case's plastic rails (A). Be sure the front of the CD-ROM drive is flush with the front of the iMac.

Replace the two screws beneath the plastic handle. They'll go in more easily if you tilt the iMac away from you.

Reattach the large multicolored cable first, then the smaller multicolored cable, then the screw that holds the smaller multicolored cable in place, then the large gray cable, and finally the smaller gray cable.

Replace the cover by slipping the plastic lip at the bottom of the cover under the rim of the iMac's case. Snap the rest of the cover into place, and replace the single screw under the handle.

Replace the cables, and turn on your iMac.

6: Install and Restore Your Software If you've upgraded the iMac's hard drive, the new drive likely contains not a shred of system software--meaning that your iMac can't boot from it. An iMac that doesn't boot is no more than an attractive curio. Here's how to make it more useful.

After switching on your iMac, you'll see a flashing folder icon with a question mark. This indicates that your iMac can't find a functioning System Folder. Insert an appropriate system-software installation disc into the CD-ROM drive--the Software Install disc that came with your iMac or a more recent installation disc, such as the Mac OS 9.1 system-software disc. The iMac should boot from this disc.

Open the Utilities folder on the disc, and launch Drive Setup. Select the iMac's hard drive in the Drive Setup window, and click on the Initialize button.

To format the drive as a single volume, click on the Initialize button (A) in the resulting window. To create partitions, click on Custom Setup and select the number of partitions you'd like from the Partitioning Scheme pop-up menu.

Run the Mac OS Install application on the CD-ROM to install a new system on the hard drive.

Go to About This Macintosh (in the Apple menu) to make sure the computer is registering your new RAM.

Finally, you can copy your backed-up data to the new hard drive and restart from your new hard drive.

1: Slot-Loading iMacs


Prepare Your Computer Before you break into your slot-loading iMac's case to replace the hard drive, you'll need to back up your data, disconnect all cables from your iMac, position the computer properly, and undo the iMac's back doors and latches.

Back up the contents of your hard drive to an external hard drive, a network, the Internet, or some form of removable media. Shut down your iMac, and disconnect all cables from it, including peripherals and its power cord.

Turn your iMac upside down on a soft surface such as a towel, so that the monitor is facing away from you and the part of the case with the handle is on the soft surface.

Use a quarter or a flathead screwdriver to open the latch on the door for RAM and AirPort access (A).

To discharge electricity that could harm your iMac, put a grounding strap around your wrist and attach it to the iMac's metal case. If you don't have a grounding strap, touch the iMac's metal case to discharge static.

Inside the case, you'll see RAM and an AirPort card (if you have one). Remove both the RAM and the AirPort card with needle-nose pliers or your fingers.

Locate the VGA port cover (B), and carefully pry it off with the flathead screwdriver.

2: Open the Case Now that you've backed up your data and laid the groundwork, you're ready for the bulk of the job: taking apart and putting together the iMac's case.

Unscrew the four retaining screws: two under the VGA port and two under the height-adjustment stand. Put the screws in a safe place.

Your next challenge is removing the iMac's bottom panel. Look closely near the bottom of the monitor for the white plastic clips.

Gently lift the bottom part of the case, from the back side of the iMac toward the monitor (A), and remove it. You may break the clips; even if you don't, it may sound as though they're breaking. (Your iMac will function with broken clips.)

Use a magnetic Phillips screwdriver to remove the four tiny screws around the outside of the metal grid that acts as a heat shield and the two on top of the heat shield (B). Take care not to drop a screw into your iMac. Leaving the screw inside could result in its tripping a wire or otherwise causing damage. Wiggle the heat shield gently while lifting it upward. It should come completely off.

3: Remove the Original Hard Drive Taking out your old hard drive is easy. Just disconnect the drive's cables, and free the drive from its housing by undoing some screws.

Locate the rectangular metal box that sits closest to the iMac's monitor and round speakers. Disconnect the data ribbon (A) and power connection (B) by tugging and wiggling them. It may take more than a gentle touch to persuade the power connector out of the socket. Just make sure you pull the connector itself and not the cable.

Loosen the four small screws on the top of the metal housing that hold your hard drive in place {imageRef("cbutton")} and put them somewhere safe. Reach into the metal box and remove the hard drive. Set it aside.

4: Install the New Hard Drive Now that you've removed the old hard drive, you're ready to install a larger-capacity hard drive. It's time to check the jumper configuration, line up the drive, and fasten the screws.

Examine your new hard drive to make sure that the jumpers (A) are set for Master or Single. If they're not set correctly, follow the directions that came with the new hard drive to reset them.

Now put the new hard drive, with the ports facing out (so you can reconnect the data ribbon and power connection), into the metal housing, and align the screw holes in the metal housing with those on the hard drive. You may want to use the flathead screwdriver to help you prop the hard drive against the metal housing.

Replace the four small screws on top of the metal housing. Tighten the screws completely only when all four screws are aligned in the hard drive properly (B).

Replace the data ribbon and the power connection. Both may seem a little resistant, but be sure to push them in until they're snug.

5: Replace the Outer Case and Install the RAM It's time to close up your iMac's case, restoring it to its original state. The RAM slot is accessible from the outside of the iMac, so you'll upgrade the RAM last.

Fit the heat shield back onto your iMac on the side closest to the VGA connector (A), and bring it down toward the hard drive.

Another tricky spot involves replacing the six small screws that fasten the metal heat shield to the bottom part of the iMac's case. Use your needle-nose pliers to help hold the tiny screws in place around the outside of the heat shield. The screw closest to the front left of the monitor is the most difficult, so do that one last.

Replace the white plastic case, starting at the iMac's monitor--where the plastic clips are--and going toward the VGA connector. Then you can replace the four screws you removed in step 2.

Now that your iMac is completely reencased, open the RAM door with the flathead screwdriver or a quarter. Use your hands to line up the RAM in the two slots, and then push it into place with your fingers (B). Replace the AirPort card, if you have one, in the same way.

6: Start Up the iMac and Restore Your Data All that's left to do is initialize your new hard drive, reinstall Mac OS, and restore the data you backed up in step 1. Unfortunately, if you made a mistake in a previous step, this is when you'll find out.

Reconnect all the cables to your iMac, and turn on the computer. When you see a flashing folder icon with a question mark, insert the Mac OS CD.

Go to the Utilities folder on the disc, and launch Drive Setup. Select the iMac's hard drive in the Drive Setup window, and click on Initialize.

To format the drive as a single volume, click on the Initialize button (A) in the resulting window. You can create partitions by clicking on Custom Setup and selecting the appropriate number of partitions from the Partitioning Scheme pop-up menu. If you plan to install OS X someday, this is a good time to set one partition aside for it. Select Mac OS Extended in the Volume Info portion of this window.

Run the Mac OS Install application on the CD-ROM to install a new system on the hard drive.

Go to About This Macintosh (in the Apple menu) to make sure the computer is registering your new RAM.

Finally, you can copy your backed-up data to your new hard drive and restart your iMac.

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