Understanding DDR3 Serial Presence Detect (SPD) Table". simmtester.com . Retrieved 12 December 2015. Addendum No. 1 to JESD79-3 - 1.35 V DDR3L-800, DDR3L-1066, DDR3L-1333, DDR3L-1600, and DDR3L-1866 (JESD79-3-1A.01) While the typical latencies for a JEDEC DDR2-800 device were 5-5-5-15 (12.5ns), some standard latencies for JEDEC DDR3 devices include 7-7-7-20 for DDR3-1066 (13.125ns) and 8-8-8-24 for DDR3-1333 (12ns).

ECC memory, which has an extra data byte lane used for correcting minor errors and detecting major errors for better reliability. Modules with ECC are identified by an additional ECC or E in their designation. For example: "PC3-6400 ECC", or PC3-8500E. [29] DocMemory (2007-02-21). "Memory Module Picture 2007". Archived from the original on 2017-06-06 . Retrieved 2022-01-05. Specification Will Encourage Lower Power Consumption for Countless Consumer Electronics, Networking and Computer Products".

DDR2 speeds

DDR3 dual-inline memory modules (DIMMs) have 240 pins and are electrically incompatible with DDR2. A key notch—located differently in DDR2 and DDR3 DIMMs—prevents accidentally interchanging them. Not only are they keyed differently, but DDR2 has rounded notches on the side and the DDR3 modules have square notches on the side. [16] DDR3 SO-DIMMs have 204 pins. [17] The DDR3L ( DDR3 Low Voltage) standard is an addendum to the JESD79-3 DDR3 Memory Device Standard specifying low voltage devices. [31] The DDR3L standard is 1.35V and has the label PC3L for its modules. Examples include DDR3L‐800 (PC3L-6400), DDR3L‐1066 (PC3L-8500), DDR3L‐1333 (PC3L-10600), and DDR3L‐1600 (PC3L-12800). Memory specified to DDR3L and DDR3U specifications is compatible with the original DDR3 standard, and can run at either the lower voltage or at 1.50 V. [32] However, devices that require DDR3L explicitly, which operate at 1.35V, such as systems using mobile versions of fourth-generation Intel Core processors, are not compatible with 1.50V DDR3 memory. [33] DDR3L is different from and incompatible with the LPDDR3 mobile memory standard. Power consumption of individual SDRAM chips (or, by extension, DIMMs) varies based on many factors, including speed, type of usage, voltage, etc. Dell's Power Advisor calculates that 4GB ECC DDR1333 RDIMMs use about 4W each. [20] By contrast, a more modern mainstream desktop-oriented part 8GB, DDR3/1600 DIMM, is rated at 2.58W, despite being significantly faster. [21] Modules [ edit ] List of standard DDR3 SDRAM modules

Shilov, Anton (2008-10-29). "Kingston Rolls Out Industry's First 2GHz Memory Modules for Intel Core i7 Platforms". Xbit Laboratories. Archived from the original on 2008-11-01 . Retrieved 2008-11-02. DDR3-xxx denotes data transfer rate, and describes DDR chips, whereas PC3-xxxx denotes theoretical bandwidth (with the last two digits truncated), and is used to describe assembled DIMMs. Bandwidth is calculated by taking transfers per second and multiplying by eight. This is because DDR3 memory modules transfer data on a bus that is 64 data bits wide, and since a byte comprises 8 bits, this equates to 8 bytes of data per transfer. McCloskey, Alan, Research: DDR FAQ, archived from the original on 2007-11-12 , retrieved 2007-10-18 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.Cutress, Ian (2014-02-11). "I'M Intelligent Memory to release 16GB Unregistered DDR3 Modules". anandtech.com . Retrieved 2015-04-20. Pc3 10600 vs. pc3 10666 What's the difference – New-System-Build, Tomshardware.com , retrieved 2012-01-23 In February 2005, Samsung introduced the first prototype DDR3 memory chip. Samsung played a major role in the development and standardisation of DDR3. [2] [3] In May 2005, Desi Rhoden, chairman of the JEDEC committee, stated that DDR3 had been under development for "about 3 years". [4] Shilov, Anton (August 16, 2010). "Next-Generation DDR4 Memory to Reach 4.266GHz – Report". XbitLabs.com. Archived from the original on December 19, 2010 . Retrieved 2011-01-03. Chang, Jaci (2004). "Design Considerations for the DDR3 Memory Sub-System" (PDF). Jedex. p.4. Archived from the original (PDF) on 2012-07-24 . Retrieved 2020-08-12.

Fully buffered modules, which are designated by F or FB and do not have the same notch position as other classes. Fully buffered modules cannot be used with motherboards that are made for registered modules, and the different notch position physically prevents their insertion. In addition to bandwidth designations (e.g. DDR3-800D), and capacity variants, modules can be one of the following: Soderstrom, Thomas (2007-06-05). "Pipe Dreams: Six P35-DDR3 Motherboards Compared". Tom's Hardware. JEDEC Solid State Technology Association announced the publication of Release 4 of the DDR3 Serial Presence Detect (SPD) document on September 1, 2011. [27] XMP extension [ edit ] JEDEC Solid State Technology Association announced the publication of JEDEC DDR3L on July 26, 2010 [35] and the DDR3U in October 2011. [36] Feature summary [ edit ] Components [ edit ]DDR3 does use the same electric signaling standard as DDR and DDR2, Stub Series Terminated Logic, albeit at different timings and voltages. Specifically, DDR3 uses SSTL_15. [13] As with earlier memory generations, faster DDR3 memory became available after the release of the initial versions. DDR3-2000 memory with 9-9-9-28 latency (9ns) was available in time to coincide with the Intel Core i7 release in late 2008, [19] while later developments made DDR3-2400 widely available (with CL 9–12cycles = 7.5–10ns), and speeds up to DDR3-3200 available (with CL 13cycles = 8.125ns). IDF: "DDR3 won't catch up with DDR2 during 2009" ". pcpro.co.uk. 19 August 2008. Archived from the original on 2009-04-02 . Retrieved 2009-06-17.

a b "What is LR-DIMM, LRDIMM Memory? (Load-Reduce DIMM)". simmtester.com. Archived from the original on 2014-09-03 . Retrieved 2014-08-29.Fractional frequencies are normally rounded down, but rounding up to 667 is common because of the exact number being 666 2⁄ 3 and rounding to the nearest whole number. Some manufacturers also round to a certain precision or round up instead. For example, PC3-10666 memory could be listed as PC3-10600 or PC3-10700. [23]