As a dual inline memory module (DIMM) (English about doppelreihiger memory block) are called memory modules for the memory of computers. In contrast to single in-line memory modules ( SIMM) lead DIMMs on the connector contacts on the front and on the back of the PCB different signals.

DIMMs are now known in a variety of designs. The more common are:

  • DIMMs with 168 contacts and two notches in the connector are generally equipped with SDRAM and feature a 64 -bit wide data bus. The precise position of the notch between the contact 40 and 41 is varied again in the sub-variants of this type and serves to detect the supply voltage provided for the module. Rather positioned on the left: 5 V, positioned centrally: 3.3V, positioned to the right: reserved for special cases. The precise position of the notch between the contact 10 and 11 is varied. More rarely, there are modules that are equipped with EDO, as well as SRAMs for use as L2 cache. To avoid confusion, they differ by slightly different positions of these two scores.
  • Dual Inline Modules with 184 contacts and a score are equipped with DDR SDRAM.
  • Dual Inline Modules with 240 contacts and a score are equipped with DDR2 SDRAM chips or DDR3 SDRAM chips.
  • Dual Inline Modules with 72 or 144 contacts ( SDRAM ), 200 contacts (DDR and DDR2 RAM) and 204 contacts (DDR3- RAM ) are used in laptops as so-called SO- DIMMs.

For specific server applications, other types were used.

Unlike SIMM modules that are set slightly obliquely in their base without force, and secured by folding over a spring latch (or sometimes set vertically and its final position is oblique ) DIMM modules with the exception of SO- DIMMs are always perpendicular to the motherboard pressed, with small lever on the socket ends when removing assist.