DIMM stands for Dual In-line Memory Module. It consists of a series of dynamic Random Access Memories (DRAMs) using miniaturized electronic circuits known as integrated circuits. The circuits are mounted on a printed circuit board, forming a single entire circuit, which is collectively called the memory module.

Dual In-line Memory Modules are designed for use in high-end workstations, servers, and personal computers. They make contact with the data bus of the computer through connectors that fit into a socket on the motherboard.

DIMMs have replaced earlier memory modules known as Single In-line Memory Modules (SIMMs) as the principal type of memory module used by Intel’s Pentium processors.

The Difference Between DIMM and SIMM

SIMMs have redundant contact on both sides of the module, so the processor can access the SIMM through either side. DIMMs, on the other hand, have unique contacts on either side of the module, hence making much better use of the connectors.

Also, standard SIMMs have a 32-bit data path, while standard DIMMs use a 64-bit data path.

Since Intel’s Pentium processors and other several other personal computers have a 64-bit data width, SIMMs have to be installed in matched pairs to fully utilize the processing power of the CPU and complete the data bus that can handle only 32-bit at a time.DIMMs were introduced to correct this inefficient method of installing memory modules.

Types of DIMM

The most common types of Dual In-line Memory Modules (DIMMs) are as follows:

1. 100-pin DIMM. It is frequently utilized for printer SDRAM (Synchronous Dynamic Random Access Memory).

Since it uses a Synchronous interface, it waits for a clock signal prior to responding to control inputs. It is synchronized with the computer’s system bus as well as with the processor.

2. 168-pin DIMM. It is utilized for SDR SDRAM (Single Data Rate Synchronous Dynamic Random Access Memory). It has the capacity to accept one command and transfer one word of data per clock cycle.

It is less frequently used for FPM (Fast Page Mode) or EDO (Extended Data Out) DRAM (Dynamic Random Access Memory) in servers or workstations.

3. 184-pin DIMM. It is utilized for DDR SDRAM (Double Data Rate Synchronous Dynamic Random Access Memory). It has the ability to achieve twice the bandwidth (the capacity to transfer data over a connection) compared to SDR SDRAM.

4. 240-pin DIMM. It is utilized for FB (Fully Buffered)-DIMM DRAM, which has the capacity to increase the speed, density and reliability of memory systems.

It can also be utilized in both DDR2 (Double-Data-Rate Two) SDRAM and DDR3 (Double-Data-Rate Three) SDRAM. They are used for high speed storage of any working data.