The iMac has two RAM expansion slots. The slots accept standard PC-100 168-pin DIMMs (dual inline memory modules) using SDRAM devices. A DIMM for a iMac can contain either 64, 128, 256, or 512 MB of memory.
IMPORTANT
The 168-pin DIMMs used in the iMac are not the same as the 144-pin SO-DIMMs used in the 233, 266, and 333 MHz iMac models.
A door on the bottom of the computer provides access to the RAM expansion slots. Before opening the bottom door, the user should place the computer face down on a soft cloth.
When the door is open, the portion of the main logic board that contains the two RAM expansion slots is visible. One slot is normally occupied by the factory-installed RAM DIMM. The other RAM expansion slot is available for a user-installed DIMM.
IMPORTANT
The user should be reminded to observe the usual precautions to avoid damage to the electronic components due to static electricity.