DDR is the acronym for Double Data Rate Synchronous DRAM
(SDRAM). DDR SDRAM memory technology is an evolutionary
technology derived from mature SDRAM technology. The secret
to DDR memory's high performance is its ability to perform
two data operations in one clock cycle - providing twice
the throughput of SDRAM.
DDR SDRAM memory technology has evolved from mainstream
PC100 and PC133. This new memory technology enables a new
generation of higher performance computer systems, including
desktops, workstations, servers, portables, as well as new
communications products such as routers and switches. DDR
memory technology is currently widely
used in high-performance graphic adapters. DDR DIMMs have the same physical dimensions as SDRAM DIMMs,
but have a different footprint that uses 184 pins compared
to 168-pin SDRAM DIMMs. Therefore, DDR memory technology is
not backward-compatible with SDRAM and requires motherboards
and systems especially designed for DDR.
You can use some of the easy tools to find your exact DDR or DDR2 Memory Upgrades for your Desktop, Laptop or Servers. Use the Memory Selector to find compatible DDR or DDR2 Memory Upgrades, or the all new system scanner tool to scan your system to find exact matching DDR RAM. If you need more help use the Live Chat Support
DDR SDRAM for desktop computers DIMMs have 184 pins (as opposed to 168 pins on SDRAM, or 240 pins on DDR2 SDRAM), and can be differentiated from SDRAM DIMMs by the number of notches (DDR SDRAM has one, SDRAM has two). DDR for notebook computers SO-DIMMs have 200 pins which is the same number of pins as DDR2 SO-DIMMs. These two specifications are notched very similarly and care must be taken during insertion when you are unsure of a correct match
DDR2 introduces some new features which allow it to ramp up to much higher speeds (with correspondingly higher bandwidth) and higher memory densities, all the while using less power. DDR2 memory uses a new form factor, a 240 pin DIMM (Dual Inline Memory Module) which is *not* compatible with current DDR memory slots. Upcoming chipsets by Intel and other manufacturers will support DDR2 specifically, and are not backwards compatible.