Apple eMac ATI Graphics (Memory Replacement) - Manual (Page 6)

eMac (ATI Graphics) and eMac (USB 2.0) Memory - 6
3. Align the replacement memory module in the memory slot, apply pressure evenly to
both top corners, and push the memory into the slot until the ejectors lock it into place.
(Figure 6)
Warning: The memory is designed to fit into the slot only one way. Be sure to align
the notches in the memory module with the small ribs inside the slot.
Figure 6