7. With the notched end of the SO-DIMM toward the contact edge side of the socket, insert the SO-DIMM(1) into the socket at an angle of about 20 degrees; then press it in firmly. Pivot the SO-DIMM downward(2) until it snaps into place.Note: If you install a memory module in only one of the two memory slots, be sure to install it in theupper slot.8. Make sure that the SO-DIMM is firmly fixed in the slot and cannot be moved easily.9. Reinstall the keyboard. For details, refer to the instructions in “Replacing the keyboard” on page 130.10. Put the battery back in place (for details, refer to the instructions in “Replacing the battery” on page119), turn the computer over again, and reconnect the cables.Checking the total amount of memory installed in your computerTo make sure that the SO-DIMM is installed correctly, do as follows:1. Turn the computer on.2. When the logo screen is displayed, press F1. The ThinkPad Setup opens. The “Installed memory” itemshows the total amount of memory installed in your computer.3. If the “Installed memory” item shows a different amount of memory from what you installed, checkwhether you have correctly followed the instructions in this section.Chapter 6. Replacing devices 147