Side-by-Side Comparison
Graphics Cards
GDDR6 vs. GDDR6X
Comparing 2 standards across 6 specifications. 6 key differences identified.
Comparing:
GDDR6
GDDR6X
GDDR6, standardized by JEDEC in July 2017 and reaching mass production in early 2018, doubled data rates over GDDR5 to as much as 16-18 Gbit/s per pin -- the current mainstream graphics memory standard for most non-flagship cards.
GDDR6X is not a JEDEC standard -- it's a proprietary memory technology Micron developed specifically in collaboration with Nvidia, first shipping in 2020 with the RTX 3080 and RTX 3090. It uses PAM4 signaling, the same two-bit-per-symbol approach PCIe 6.0 later adopted, to reach 19-21 Gbit/s per pin.
Specification Comparison Table
6 Parameters| Parameter / Spec | ||
|---|---|---|
|
Max Bandwidth / Data Rate
|
Up to 16 Gbit/s per pin (18 Gbit/s in mass-production variants) | 19–21 Gbit/s per pin |
|
JEDEC Standard
|
July 2017 | — |
|
Mass Production
|
January 2018 | — |
|
Standard
|
— | Proprietary (Micron, developed with Nvidia) -- not JEDEC |
|
Signaling
|
— | PAM4 (2 bits per symbol, vs. GDDR5/6's 1-bit NRZ) |
|
Introduced
|
— | 2020 (Nvidia RTX 3080 and RTX 3090) |