It turns out that the upcoming Radeon RX 7900 GRE (Golden Rabbit Edition) is built on the mysterious Navi 31 + Navi 32 hybrid GPU that's been in the news for a few weeks now. AMD has reportedly developed its answer to NVIDIA's AD103 silicon in the form of a new MCM that combines the 5 nm GCD of the "Navi 31," along with the substrate of the "Navi 32," which is physically smaller, and only has four 6 nm MCDs. This hybrid MCM could power AMD's mobile Radeon RX 7900 series. The chip physically only has a 256-bit wide GDDR6 memory interface. AMD felt the need for such a contraption as the "Navi 31" is likely too big for mobile platforms, and because the "Navi 32" GCD with its 60 CU (3,840 stream processors) might prove inadequate against a maxed out AD104 or cut-down AD103.

VideoCardz caught whiff of the new GPU by comparing the back sides of the Sapphire RX 7900 GRE from yesterday's leak, with that of the production Sapphire RX 7900 XT/XTX NITRO+. There are visible differences in the layout of the SMDs, and the reinforcement brace behind the GPU has a square cutout, compared to the rectangular one behind the "Navi 31" powering the RX 7900 XT/XTX NITRO+. On the RX 7900 GRE, the GCD is configured with 84 CU, or the same core-config as the RX 7900 XT, albeit with the narrower 256-bit memory interface, and 64 MB of Infinity Cache memory. It's highly likely that AMD uses this GPU to carve out the Radeon RX 7800 XT (with fewer than 84 but higher than 60 CU); while creating the RX 7800 with a maxed out "Navi 32," and the RX 7700 series with a cut-down "Navi 32" (including by narrowing the memory bus width to 192-bit by disabling one of the four MCDs). AMD is reportedly planning to launch the RX 7900 GRE in China, on July 28, 2023.