AMD Radeon RX 7900 XT to Feature 384MB of L3, 192MB 3D Stacked Cache, 384-bit Bus Across 7 MCD Chiplets [Rumor]

AMD’s next-gen Radeon RX 7900 XT flagship GPU will leverage a bunch of advanced process and packaging technologies, including TSMC 5nm and 6nm nodes. Featuring the Navi 31 core, it will pack a total of seven dies. The primary Graphics Compute Die (GCD) will be based on the 5nm process with up to 12,288 stream processors across 96 CUs and 48 WGPs. The remaining six dies will be the MCDs (Memory Complex Dies) fabbed on the N6 node. Each of these will consist of a 64-bit memory controller paired with 32MB of L3 “Infinity” Cache.

GPU NameRX 7700 XT (Navi 33)RX 7800 XT (Navi 32)RX 7900 XT (Navi 31)RX 7950 XT (Navi 30?)
Process Node6nm5nm + 6nm5nm + 6nm5nm + 6nm
Die Config6nm x15nm x1, 6nm x45nm x1, 6nm x55nm x1, 6nm x6
Shader Engines2466
Memory Bus128-bit256-bit320-bit?384-bit?
Memory Capacity8GB16GB20GB?24GB?
Infinity Cache64MB128MB192MB192MB?
LaunchQ4 2022Q1 2023Q4 20222023

For the fully enabled Navi 31 GPU, this results in a total L3 cache of 192MB and a bus width of 384-bit along with 16-32GB of GDDR6 18Gbps memory. According to @Kepler_L2 (Twitter), there will be certain models with even more Infinity Cache. These cache dies will be 3D stacked on the MCDs, each contributing 32MB for an overall SRAM of 384MB.

Courtesy: Olrak (Twitter)

This should confer the Radeon RX 7900 XT with incredible memory bandwidth, much higher than the RTX 4090, internally. The latter should still be faster on account of the higher ALU count but I reckon the delta won’t be significant, even at higher resolutions.



Computer hardware enthusiast, PC gamer, and almost an engineer. Former co-founder of Techquila (2017-2019), a fairly successful tech outlet. Been working on Hardware Times since 2019, an outlet dedicated to computer hardware and its applications.