It is the higher-speed successor to DDR and DDR2 and predecessor to DDR4 synchronous dynamic random-access memory (SDRAM) chips.

DDR3 SDRAM is neither forward nor backward compatible with any earlier type of random-access memory (RAM) because of different signaling voltages, timings, and other factors.

IDC stated in January 2009 that DDR3 sales would account for 29% of the total DRAM units sold in 2009, rising to 72% by 2011.

[8] The primary benefits of DDR4 compared to DDR3 include a higher standardized range of clock frequencies and data transfer rates[9] and significantly lower voltage.

[10] According to JEDEC,[11]: 111  1.575 volts should be considered the absolute maximum when memory stability is the foremost consideration, such as in servers or other mission-critical devices.

In addition, JEDEC states that memory modules must withstand up to 1.80 volts[a] before incurring permanent damage, although they are not required to function correctly at that level.

It is also misleading because various memory timings are given in units of clock cycles, which are half the speed of data transfers.

DDR3 does use the same electric signaling standard as DDR and DDR2, Stub Series Terminated Logic, albeit at different timings and voltages.

[2] Products in the form of motherboards appeared on the market in June 2007[14] based on Intel's P35 "Bearlake" chipset with DIMMs at bandwidths up to DDR3-1600 (PC3-12800).

The purpose of UniDIMMs is to handle the transition from DDR3 to DDR4, where pricing and availability may make it desirable to switch RAM type.

Power consumption of individual SDRAM chips (or, by extension, DIMMs) varies based on many factors, including speed, type of usage, voltage, etc.

[20] By contrast, a more modern mainstream desktop-oriented part 8 GB, DDR3/1600 DIMM, is rated at 2.58 W, despite being significantly faster.

[11]: 157–165 All RAM data rates in-between or above these listed specifications are not standardized by JEDEC—often they are simply manufacturer optimizations using higher-tolerance or overvolted chips.

[24] Alternative naming: DDR3 modules are often incorrectly labeled with the prefix PC (instead of PC3), for marketing reasons, followed by the data-rate.

Release 4 of the DDR3 Serial Presence Detect (SPD) document (SPD4_01_02_11) adds support for Load Reduction DIMMs and also for 16b-SO-DIMMs and 32b-SO-DIMMs.

JEDEC Solid State Technology Association announced the publication of Release 4 of the DDR3 Serial Presence Detect (SPD) document on September 1, 2011.

[28] In addition to bandwidth designations (e.g. DDR3-800D), and capacity variants, modules can be one of the following: Both FBDIMM (fully buffered) and LRDIMM (load reduced) memory types are designed primarily to control the amount of electric current flowing to and from the memory chips at any given time.