Toshiba Satellite A40 User Manual page 127

Optional Devices
8. Lift into the left the insulation sheet covering the memory module and
secure the sheet with tape to keep it out of your way.
Do not touch the connectors on the memory module or on the computer.
Debris on the connectors may cause memory access problems.
The slot A is reserved for main memory. Use the slot B for expanded
memory. If only one card is installed, use the slot A.
Lifting into the left the insulation sheet.
TOSHIBA A40 Series 8 7