Micron has seemingly confirmed in a blog post that they are indeed preparing the next-generation GDDR6X memory which would be featured on NVIDIA's Ampere based GeForce RTX 30 series cards including the flagship RTX 3090. The next-generation GDDR6X memory interface will deliver higher bandwidth and improved performance efficiency compared to the existing GDDR6 memory that is incorporated by the GeForce RTX 20 'Turing' and Radeon RX 5000 'RDNA' graphics cards.

NVIDIA GeForce RTX 30 Series Confirmed To Featured GDDR6X Memory - Up To 21 Gbps Clocks & 1 TB/s Bandwidth For Flagship GeForce RTX 3090 Graphics Card

As per Micron, the GDDR6X memory interface is an evolution of the existing GDDR6 memory dies which are designed in collaboration with NVIDIA to power its next-generation Ampere GeForce RTX 30 series lineup. We have heard rumors about the GDDR6X memory interface till now but it looks like the GDDR6X has been the second-best kept secret with the first one being the GeForce RTX 30 series lineup itself.

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. via Micron (Videocardz)

This adds in

In the blog post, Micron mentions not only the specifications of its GDDR6X DRAM but also the RTX 3090 graphics cards which also confirms the existence of this specific card. The GDDR6X memory is purely designed as an ultra-bandwidth solution which is made up of 8 Gb dies that deliver speeds of up to 21 Gb/s. In the case of the GeForce RTX 3090 which would feature a 384-bit bus interface, we can expect a total bandwidth of 1 TB/s which is insane amounts for a flagship tier graphics card.

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 technology for Ultra-Bandwidth Solutions. PAM4 has the potential to drive even more improvements in data rate. via Micron (Videocardz)

Micron mentions that the NVIDIA GeForce RTX 3090 will feature 12 GDDR6X DRAM dies for a total of 12 GB memory however it looks like NVIDIA has changed that much and the card will be offering double the expected memory of up to 24 GB. This was also seen in the recently leaked PCB shot that shows the card with dual-sided DRAM dies. The GDDR6X memory dies are rated at 19 Gbps & 21 Gbps so the lineup itself can utilize from different speeds depending on their market segment.

NVIDIA GeForce RTX 30 Series Ampere 'GDDR6X' Memory Specs (Preliminary):

NVIDIA GeForce RTX 30 "Ampere' Graphics Card Rumored Lineup: