Lenovo 7812, Hardware Maintenance Manual

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Replacing a memory module
This procedure describes how to remove and replace a memory module.
Installing memory
This computer either has two or four connectors for installing double data rate 2 dual
inline memory modules (DDR2 DIMMs). System boards with two connectors can
accommodate a maximum of 2.0 GB of system memory. System boards with four
connectors can accommodate a maximum of 4.0 GB of system memory.
When installing memory modules, the following rules apply:
v If you are replacing a memory module on a system board with four memory connectors,
at least one memory module must be installed in the first memory channel (in either
memory connector 1 or memory connector 2). See “Locating parts on the system board”
on page 125for more information.
v
Use 1.8 V, 240-pin, double data rate 2 synchronous dynamic random access memory
(DDR2 SDRAM).
v
Use 256 MB, 512 MB, or 1 GB memory modules in any combination.
Note: Only DDR2 SDRAM DIMMs can be used.
1. Remove the computer cover. See “Removing the cover” on page 123.
Note: For this procedure, it helps to lay the computer on its side.
2.
Locate the memory module connectors. See “Locating parts on the system
board” on page 125.
3. Remove the memory module being replaced by opening the retaining clips as
shown.
4. Position the new memory module over the memory connector. Make sure the
notch
1
on the memory aligns correctly with the connector key
2
on the
system board. Push the memory module straight down into the connector until
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Hardware Maintenance Manual