Based on AMD's RDNA2 architecture, the chip reportedly uses GDDR6 memory and may offer hardware-based ray tracing support. Cards based on the chip will likely have a 384-bit or 512-bit memory bus with at least 12GB or 16GB GDDR6 memory.
Not a lot of other details, other than that RDNA2 is rumored to be more energy-efficient than the previous generation. Either way, such a large chip will definitely have a high TDP.
Via: 3DCenter and WCCF Tech