GDDR SDRAM

Graphics DDR SDRAM (GDDR SDRAM) is a type of synchronous dynamic random-access memory (SDRAM) specifically designed for applications requiring high bandwidth, e.g. graphics processing units (GPUs). GDDR SDRAM is distinct from the more widely known types of DDR SDRAM, such as DDR4 and DDR5, although they share some of the same features—including double data rate (DDR) data transfers. As of 2023, GDDR SDRAM has been succeeded by GDDR2, GDDR3, GDDR4, GDDR5, GDDR5X, GDDR6, GDDR6X and GDDR6W.

Generations

See also: Synchronous dynamic random-access memory § Timeline

• 
  Hynix GDDR SDRAM
• 
  A Samsung GDDR3 256MBit package
• 
  A 512 MBit Qimonda GDDR3 SDRAM package
• 
  Inside a Samsung GDDR3 256MBit package

DDR SGRAM

GDDR was initially known as DDR SGRAM (double data rate synchronous graphics RAM). It was commercially introduced as a 16 Mb memory chip by Samsung Electronics in 1998.

GDDR2

Main article: GDDR2 SDRAM

GDDR3

Main article: GDDR3 SDRAM

GDDR4

Main article: GDDR4 SDRAM

GDDR5

Main article: GDDR5 SDRAM

See also: GDDR5X

GDDR6

Main article: GDDR6 SDRAM

See also: GDDR6X and GDDR6W

GDDR7

Main article: GDDR7 SDRAM

Table of transfer rates

Module type	Chip type	Memory clock	Transfers/s	Transfer rate
?	GDDR2	500 MHz	?	128 Gbit/s	16.0 GB/s
64 lanes	GDDR3	625 MHz	2.5 GT/s	159 Gbit/s	19.9 GB/s
64 lanes	GDDR4	275 MHz	2.2 GT/s	140.8 Gbit/s	17.6 GB/s
64 lanes	GDDR5	625–1125 MHz	5–9 GT/s	320–576 Gbit/s	40–72 GB/s
64 lanes	GDDR5X	625–875 MHz	10–12 GT/s	640–896 Gbit/s	80–112 GB/s
64 lanes	GDDR6	875–1125 MHz	14–18 GT/s	896–1152 Gbit/s	112–144 GB/s
64 lanes	GDDR6X	594–656 MHz	19–21 GT/s	1216–1344 Gbit/s	152–168 GB/s
?	GDDR6W	?	?―22 GT/s	?	?
?	GDDR7	?	?―36 GT/s	?	?

See also

• Video random access memory
• Double data rate