Toshiba Satellite C640 - Manual (Page 63)

User’s Manual 3-18
Hardware, Utilities and Options
Removing the cover
6. Insert the memory module into the connector on the computer. Press
the module carefully and firmly to ensure a solid connection.
7. Push the module down so that it lies flat and is secured by two latches.
Inserting the memory module
Do not touch the connectors on the memory module or on the computer.
Debris on the connectors may cause memory access problems.