It turns out that the mysterious Navi 31 + Navi 32 hybrid GPU that has been in the news for a few weeks is the foundation of the upcoming Radeon RX 7900 GRE (Golden Rabbit Edition). In the shape of a new MCM that combines the 5 nm GCD of the “Navi 31” with the substrate of the “Navi 32,” which is physically smaller and only has four 6 nm MCDs, AMD has apparently produced its response to NVIDIA’s AD103 silicon. The mobile Radeon RX 7900 series from AMD might be powered by this hybrid MCM. The chip’s physical GDDR6 memory interface is only 256 bits wide. The “Navi 31” is probably too large for mobile platforms, and AMD saw the need for such a device since the “Navi 32” GCD, with its 60 CU (3,840 stream processors), might not be sufficient against an AD104 or AD103 that has been scaled back or maxed out.

By contrasting the back sides of the Sapphire RX 7900 GRE from yesterday’s leak with those of the production Sapphire RX 7900 XT/XTX NITRO+, VideoCardz was able to detect the new GPU. When compared to the rectangular cutout behind the “Navi 31” powering the RX 7900 XT/XTX NITRO+, the reinforcement brace behind the GPU has a square cutout, and there are obvious variations in the layout of the SMDs. The GCD on the RX 7900 GRE is set up with 84 CU, or the same core configuration as the RX 7900 XT, but with a 64 MB of Infinity Cache memory and a narrower 256-bit memory interface. It’s very likely that AMD will use this GPU to create the Radeon RX 7800 XT (with fewer than 84 but higher than 60 CU), the RX 7800 with a maxed-out “Navi 32,” and the RX 7700 series with a scaled-down “Navi 32” (including by narrowing the memory bus width to 192-bit by disabling one of the four MCDs). On July 28, 2023, AMD is apparently preparing to introduce the RX 7900 GRE in China.