Dell Inspiron 20 (3048, Early 2014) - Manual (Page 33)

Procedure
NOTE: If you are installing only one memory module, insert the memory
module in the memory-module slot marked as DIMM1.
1 Align the notch on the memory module with the tab on the memory-
module slot.
2 Insert the memory module into the memory-module slot, and 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.
1 notch 2 tab
3 memory-module slot
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