For use in computers, DDR2 SDRAM is supplied in DIMMs with 240 pins and a single locating notch. Laptop DDR2 SO-DIMMs have 200 pins and often come identified by an additional S in their designation. DIMMs are identified by their peak transfer capacity (often called bandwidth).

Feb 28, 2025 · What’s the difference between SDRAM, DDR, DDR2, DDR3, DDR4 and DDR5? Discover and compare the different generations of RAM with Crucial.

DDR2 Memory has 120 gold fingers on one side (240 on both sides), 64 pins on the left side of the notch and 56 pins on the right side of the notch; DDR3 memory single-sided gold finger is also 120 (240 on both sides), the left side of the gap is 72 pins, and the right side of the gap is 48 pins.

DDR, DDR2, DDR3, DDR4 and DDR5 all have different pin counts and/or different notch positions, and none of them are forward compatible or backward compatible. DDR5 SDRAM is the most recent type of DDR memory and has been in use since 2020.

DDR2: 240-pin (DIMM), 200-pin (SO-DIMM), and 214-pin (micro DIMM). DDR3: 240 pins (DIMM), 204 pins (SO-DIMM), and 214 pins (micro DIMM). DDR4: 288-pin (DIMM), 256-pin (SO-DIMM).

The notch on DDR2 DIMMs is in a different position than DDR DIMMs, and the pin density is slightly higher than DDR DIMMs. DDR2 is a 240-pin module, DDR is a 184-pin module. Faster DDR2 DIMMs though, are compatible with slower DDR2 DIMMs.

DDR2 SDRAM DIMM 240 pin. DDR: Double Data Rate; DIMM: Dual Inline Memory Module; SDRAM: Synchronous Dynamic Random Access Memory, Synchronous to Positive Clock Edge. PIN CONFIGURATIONS (Front side / back side)

Though DDR2 modules have the same basic dimensions as DDR modules, they have different voltages and pin configurations. Because of these differences, DDR2 modules have a different key (a notch in the connector) to prevent them from being inserted into an incompatible socket.

Jun 6, 2022 · Pinout of DDR2 DIMM Unbuffered Module (240 pin) and layout of 240 pin DIMM DDR2 connector

Jan 4, 2023 · Dual Inline Memory Module (DIMM), SODIMM, and MicroDIMM are all form factors of memory modules used across different devices. Their lengths and pin configuration varies. However, their performance is defined by their DDR type.