Samsung has started sampling high-speed 24 Gbps-rated GDDR6 memory chips. Just to be clear, these are standard GDDR6 chips built to JEDEC-specifications, and not GDDR6X, a derivative standard co-developed by NVIDIA and Micron leveraging PAM4 signaling. The 24 Gbps chips by Samsung can be used by both NVIDIA and AMD, if their GPU designs can handle the data-rates. The specific part number for the chip is "K4ZAF325BC-SC24." This chip has a density of 16 Gb (2 GB), which means 8 of these make up 16 GB across a 256-bit wide memory bus, and 12 of these make 24 GB across a 384-bit bus.
At 24 Gbps, these chips offer 50% more bandwidth than 16 Gbps, and 71% more than 14 Gbps. A hypothetical 6 nm refresh of the "Navi 21" paired with these chips, would hence have 768 GB/s of memory bandwidth on top of its Infinity Cache bandwidth, compared to 512 GB/s on the current Radeon RX 6800 XT. Since the chip is sampling, it’s likely that both AMD and NVIDIA have their hands on it. There’s no word on when the chip hits mass-production, but this could definitely happen within 2022.
