First up, it's rumored that the Navi 31 GPU has a maximum of 15360 cores. This chip will reportedly be used for AMD's next flagship, and could be known as the Radeon RX 7900 XT if the firm sticks to the current naming scheme. Navi 31 allegedly uses a multi-chip module (MCM) design with two dies.
It's said that AMD is getting rid of the compute units (CU) concept. Instead, Navi 31 reportedly has 30 RDNA Workgroup Processors (WGP).
Possibly an interesting change to the design is also the supposed lack of Compute Units. The GPU would be split into workgroups instead of workgroups containing compute units. This shouldn’t really change much in terms of design complexity, but it is an interesting change nonetheless.Infinity Cache is rumored to be quite a bit higher. While the current generation has 192MB, the Navi 31 may have 256MB or even 512MB.
Don't expect Navi 31 anytime soon, though. It's still at least one year removed from us.