what is DIMM key - the small cut-out notch at the bottom of the PCB of a DIMM that is used to correctly insert the DIMM with proper orientation for electrical connections. The key also is used to prevent DIMMs of different DRAM technology and voltage from accidentally being inserted into the wrong system.

RAMpedia is a DRAM memory encyclopedia and reference tool
to help computer hardware board designers with DRAM memory subsystems.
This information is provided as a courtesy by Virtium Technology.
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