Dell Alienware 15 (Early 2015) - Manual (Page 23)

2 Slide the memory module firmly into the slot at an angle 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 securing clips (2) 2 notch
3 tab 4 memory modules (2)
5 memory-module slot
Post-requisites
Replace the base panel .
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