is a type of VRAM
is a type of synchronous dynamic random-access memory (SDRAM) specifically designed for applications requiring high bandwidth, e.g. GPUs)
is distinct from the more widely known types of DDR SDRAM (e.g. DDR4 and DDR5)
as of 2023, GDDR SDRAM has been succeeded by GDDR2, GDDR3, GDDR4, GDDR5, GDDR5X, GDDR6, GDDR6X and GDDR6W

Subpages

Versions

Version	Release	I/O Clock	Bus Width per Chip	Typical Capacity per Chip	Max Bandwidth per Chip	Voltage	Notes / First GPUs
GDDR1	1998	166–400 MHz	32 bits	32–128 MB	1.3–1.6 GB/s	2.5V	Early 3D graphics memory, used in NVIDIA RIVA TNT2, ATI Rage 128
GDDR2	2001	200–400 MHz	32 bits	32–128 MB	1.6–3.2 GB/s	2.5V	Limited adoption, higher signaling rate than GDDR1
GDDR3	2003	400–800 MHz	32 bits	128–512 MB	3.2–6.4 GB/s	1.8V	Widely used; NVIDIA GeForce 6/7, ATI Radeon X series
GDDR4	2005	800–1000 MHz	32 bits	256–512 MB	6.4–8 GB/s	1.5V	Short-lived; ATI Radeon X1000 series
GDDR5	2007	1000–2000 MHz	32 bits	512 MB – 1 GB	8–16 GB/s	1.5V	Mainstream adoption; NVIDIA GeForce 8800 GTX, Radeon HD 4000
GDDR5X	2016	1250–1400 MHz	32 bits	1–2 GB	10–14 GB/s	1.35V	High-bandwidth variant of GDDR5; NVIDIA Pascal GPUs
GDDR6	2018	1750–2000 MHz	32 bits	1–2 GB	14–16 GB/s	1.35V	Widely used in gaming GPUs; RTX 20 series, AMD RX 5000
GDDR6X	2020	1900–2200 MHz	32 bits	1–2 GB	19–21 GB/s	1.35–1.45V	Uses PAM4 signaling for higher bandwidth; NVIDIA RTX 30 series
GDDR7	2023–2024	3200–4000 MHz (effective)	32 bits	2–4 GB	25–32 GB/s	~1.1–1.2V	Latest generation; very high bandwidth, supports next-gen GPUs