iMac (Early 2008): Installing or replacing memory

The iMac (Early 2008) computer has two, side-by-side SDRAM slots in the bottom of the computer, and comes with at least 1 GB DDR2 SDRAM installed in one slot.

The maximum amount of RAM you can install in the computer is 4 GB (a 2 GB SO-DIMM in each slot).

You can use Small-Outline dual inline memory modules (SO-DIMMS) that meet all of these criteria:

• PC2-6400
• Unbuffered
• Nonparity
• 200-pin
• 800 MHz
• DDR2
• SDRAM

You can use RAM module sizes of 1 GB or 2 GB in each slot.

DIMMs with any of the following features are not supported in the iMac (Early 2008) computer:

• Registered or buffered
• PLLs
• ECC
• parity
• EDO RAM

To install memory into the bottom slot, follow these instructions:

1. Turn your computer off by choosing Shut Down from the Apple menu.
2. Disconnect all cables and the power cord from your computer.
3. Place a soft, clean towel or cloth on the desk or surface to prevent scratching the LCD display. Hold the sides of the computer and slowly lay the computer face down.
4. Using a Phillips screwdriver, remove the RAM access door in the bottom of the computer and set it aside.
   
5. Untuck the tab in the memory compartment. If you are replacing a memory module, untuck the tab and pull it to eject any installed memory module.
6. Insert your new or replacement RAM SO-DIMM into the empty slot, keeping in mind the orientation of the keyway of the SO-DIMM as shown above. Once inserted, press the DIMM up into the slot. You'll hear a slight click when the memory is seated correctly.
   
7. Tuck the tabs above the memory DIMMs, and re-install the memory access door.
   
8. Stand the computer back to its upright position.
9. Reconnect the power cord and all other cables to the computer and power on the computer.

For more information about the SDRAM in the iMac (Early 2008) computer, see this article.