If the rumor is accurate, AMD will have a Navi21 GPU based card with 16GB video memory and a Navi22 model with 12GB. It's unknown if these are full die or cut down SKUs. This means AMD's cards will have more memory than the launch models of NVIDIA's Ampere lineup. At the moment, there's only a 10GB GeForce RTX 3080 but it's pretty much confirmed that a 20GB version will follow later this year.
AMD will reveal its Big Navi video cards on October 28th.
????
— _rogame (@_rogame) September 17, 2020
I've now got confirmation for both :
> Navi21 16GB VRAM
> Navi22 12GB VRAM
I have no idea if these are full die or cut down SKUs