Micron confirms NVIDIA Ampere cards use GDDR6X, GeForce RTX 3090 has 12GB

Memory maker Micron officially spilled the beans about the memory subsystem of NVIDIA's upcoming RTX 30 series. These Ampere-based desktop cards, which are expected to be introduced on September 1st, will use GDDR6X memory chips from Micron.

This was rumored for quite some time now, but up until now there was no official confirmation about the existence of GDDR6X. Not only that, but Micron also confirmed that NVIDIA will indeed release a card named "GeForce RTX 3090".

That model will feature 12 GDDR6X memory chips, good for a total of 12GB GDDR6X memory. That's lower than what was suggested by some leaks that hit the web earlier this week. If NVIDIA uses the fastest 21Gbps implementation of Micron's GDDR6X, this results in a bandwidth of 1008GB/s! With 19Gbps the bandwidth would be 912GB/s.

Micron says a 24Gbps version of its GDDR6X will follow in 2021. For comparison, the fastest version of Micron's GDDR6 offers a maximum of 16Gbps.

Perhaps the most important result of GDDR5X was that it provided the framework for GDDR6. GDDR6 was introduced in the fall of 2018 and immediately became the market leader in performance. Micron was the launch partner of NVIDIA in 2018 and of AMD in 2019 with 8Gb GDDR6, delivering the high performance the market demanded. GDDR6 is still relatively early in its projected life span, but its current maximum data rate per pin is 16Gb/s. The maximum projected system bandwidth using GDDR6 is 768GB/s (32-bit interface, 12 components and 16Gb/s per pin data rate). GDDR6 is not only an Ultra-Bandwidth Solution but also a cost-optimized one, which can be used in a variety of applications.

In Summer of 2020, Micron announced the next evolution of Ultra-Bandwidth Solutions in GDDR6X. Working closely with NVIDIA on their Ampere generation of graphics cards, Micron’s 8Gb GDDR6X will deliver up to 21Gb/s (data rate per pin) in 2020. At 21Gb/s, a graphic card with 12pcs of GDDR6X will be able to break the 1TB/s of system bandwidth barrier! Micron’s roadmap also highlights the potential for a 16Gb GDDR6X in 2021 with the ability to reach up to 24Gb/s. GDDR6X is powered by a revolutionary new PAM4 modulation technologyfor Ultra-Bandwidth Solutions. PAM4 has the potential to drive even more improvements in data rate.