DDR4 SDRAM-Features-circuit board pcb
|Two 8 GiB DDR4-2133 ECC 1.2 V RDIMMs[a]|
|Type||Synchronous dynamic random-access memory (SDRAM)|
|Release date||September 2014|
In computing, DDR4 SDRAM, an abbreviation for double data rate fourth-generation synchronous dynamic random-access memory, is a type of synchronous dynamic random-access memory (SDRAM) with a high bandwidth ("double data rate") interface.
Released to the market in 2014, it is one of the latest variants of dynamic random-access memory (DRAM), some of which have been in use since the early 1970s, and a higher-speed successor to the DDR2 and DDR3 technologies.
DDR4 is not compatible with any earlier type of random access memory (RAM) due to different signaling voltages, physical interface and other factors.
DDR4 SDRAM was released to the public market in Q2 2014, focusing on ECC memory, while the non-ECC DDR4 modules became available in Q3 2014, accompanying the launch of Haswell-E processors that require DDR4 memory.
The primary advantages of DDR4 over its predecessor, DDR3, include higher module density and lower voltage requirements, coupled with higher data rate transfer speeds. The DDR4 standard theoretically allows for DIMMs of up to 512 GiB in capacity, compared to DDR3's theoretical maximum of 128 GiB per DIMM.
DDR4 operates at a voltage between 1.2 V and 1.4 V with a frequency between 800 and 4266 MHz, compared to frequencies between 400 and 1067 MHz and voltage requirements of 1.5 or 1.65 V of DDR3. Due to the nature of DDR, speeds are typically advertised as doubles of these numbers (DDR3-1600 and DDR4-2400 are common). Although a low-voltage standard has yet to be finalized (as of August 2014), it is anticipated that low-voltage DDR4 will run at a voltage of 1.05 V, compared to DDR3's low-voltage standard (DDR3L) which requires 1.35 V to operate.