Dell P126G Service Manual page 22

Steps
1. Lift the flap to access the memory-module slot.
2. Align the notch on the memory module with the tab on the memory-module slot.
3. Slide the memory module firmly at an angle, into the memory-module slot.
4. Press the memory module down until it clicks into place.
NOTE: If you do not hear the click, remove the memory module and reinstall it.
NOTE: Repeat step 2 to step 4 to install any other memory modules in your computer.
Next steps
1. Install the base cover.
2. Follow the procedure in
22 Removing and installing components
After working inside your computer.