Advantech SIMB-M21 User Manual page 24

2. Align a SO-DIMM on the socket such that the notch on the SO-DIMM matches
the break on the socket.
DDR3 SO-DIMM notch
3. Firmly insert the SO-DIMM into the socket until the retaining clips snap back in
place and the SO-DIMM is properly seated.
Important! 

SIMB-M21 User Manual
Unlocked retaining clip
Locked retaining clip
A DDR3 SO-DIMM is keyed with a notch so that it fits in only one
direction. DO NOT force a SO-DIMM into a socket to avoid damag-
ing the SO-DIMM.
The DDR3 SO-DIMM sockets do not support DDR SO-DIMMs. DO
NOT install DDR2 SO-DIMMs to the DDR3 SO-DIMM socket.
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