Please perform the following steps as shown in the pictures below.
Note: Loosen the screws [1], but do not remove them.
Note: If only one DIMM is used on the computer you are servicing, the card must be installed in SLOT-0 ([a]), but not in SLOT-1 ([b]).
Memory installation
When installing: Insert the notched end of the DIMM into the socket. Press the DIMM firmly, and pivot it until it snaps into the place. Make sure that it is firmly fixed in the slot and does not move easily.