Editing DIMM (section)

== History ==
DIMMs (Dual In-line Memory Module) were a 1990s upgrade for [[SIMM]]s (Single In-line Memory Modules)<ref>{{cite book | url=https://books.google.com/books?id=zWrZY1OgTPsC&dq=dimm+simm+ram&pg=PA576 | title=The X86 Microprocessors: Architecture and Programming (8086 to Pentium) | isbn=9788131732465 | last1=Lyla | first1=Das B. | date=September 2010 | publisher=Pearson Education India }}</ref><ref>{{Cite book|url=https://books.google.com/books?id=gXaRdKyD4PsC&dq=so+dimm+1995&pg=PA334|title=Upgrading and Repairing PCs: Upgrading and Repairing_c21|first=Scott|last=Mueller|date=March 7, 2013|publisher=Que Publishing|isbn=9780133105360|via=Google Books|access-date=December 26, 2023|archive-date=September 17, 2024|archive-url=https://web.archive.org/web/20240917213349/https://books.google.com/books?id=gXaRdKyD4PsC&dq=so+dimm+1995&pg=PA334#v=onepage&q=so%20dimm%201995&f=false|url-status=live}}</ref> as [[Intel]] [[P5 (microarchitecture)|P5]]-based [[Pentium]] processors began to gain market share. The Pentium had a 64-bit [[bus (computing)|bus]] width, which would require SIMMs installed in matched pairs in order to populate the data bus. The processor would then access the two SIMMs in parallel.

DIMMs were introduced to eliminate this disadvantage. The contacts on SIMMs on both sides are redundant, while DIMMs have separate electrical contacts on each side of the module.<ref>{{cite book | url=https://books.google.com/books?id=SrP3aWed-esC | title=Memory Systems: Cache, DRAM, Disk | isbn=9780080553849 | last1=Jacob | first1=Bruce | last2=Wang | first2=David | last3=Ng | first3=Spencer | date=28 July 2010 | publisher=Morgan Kaufmann }}</ref> This allowed them to double the SIMMs 32-bit data path into a 64-bit data path.<ref name="auto1">{{cite book | url=https://books.google.com/books?id=E1p2FDL7P5QC&dq=simm+32+bits+dimm+64+bits&pg=PA442 | title=Upgrading and Repairing PCS | isbn=9780789729743 | last1=Mueller | first1=Scott | date=2004 | publisher=Que | access-date=2023-12-26 | archive-date=2024-09-17 | archive-url=https://web.archive.org/web/20240917213304/https://books.google.com/books?id=E1p2FDL7P5QC&dq=simm+32+bits+dimm+64+bits&pg=PA442#v=onepage&q=simm%2032%20bits%20dimm%2064%20bits&f=false | url-status=live }}</ref>

The name "DIMM" was chosen as an acronym for ''Dual In-line Memory Module'' symbolizing the split in the contacts of a SIMM into two independent rows.<ref name="auto1"/> Many enhancements have occurred to the modules in the intervening years, but the word "DIMM" has remained as one of the generic terms{{clarify|date=March 2025}} for a computer memory module.