The latest industry leaks come from a very reliable source, @Kopite7kimi who mentioned that the upcoming AMD RX 7900 XT with Navi 31 will have a total of 7 crispsdivided into 1 GCD at 5 nm and 6 MCDs at 6 nm. As a result, we would have a graph with a total of 12,288 stream processors distributed over a total of 96 compute units (CU)which would mean that the RX 7900 XT will finally be a monolithic chip, a change from previous leaks which mentioned it would be 2 GCDs and therefore eliminated the possibility of having 2 graphics chips on the same PCB .
It was only last year when we started to see the first rumors of future AMD graphics, where its highest range, the RX 7900 XT, was postulated as a graphics card that would feature 2 graphics chips on its PCB.
1GCD+6MCD, not 2GCD.
– kopite7kimi (@kopite7kimi) May 9, 2022
However, as we see now, the data has changed, ranging from 2 GCD + 4 MCD according to rumors a few months ago at 1 GCD + 6 GCD in current leakage. Remember that the GCD (Graphics Compute Die) would mean the die where the WGP and its consequent CUs, caches and main buses are housed, but…
AMD Navi 31 and its chiplets, an attempt to copy Intel Ponte Vecchio?
What is the point here to understand this? AMD’s design is still unknown, you can really go for something similar to the MI250X or go for a design similar to the Ponte Vecchio, which is what it looks like AMD is trying to do.
And it is that the similarities are quite similar with a very red team touch, where one GDC would be used instead of two and eventually the L2 and L3 would be exported to these MCDs with the Infinity Cache as Intel partially does with its RAMBO Tile Cover. In this case, the main difference is that AMD will not use HBM as a memory technology, but will stick with the cheaper GDDR6X.
Regarding the MCD (Memory Control Die), it would be the equivalent of VRAM memory access controllers, but instead of integrating it, it seems that it will be simple modules with cache and Infinity Hide where this would happen at 256-512 MB. This amount of Infinity Cache would be reduced in other AMD graphics, where for example the RX7800XT (Navi 32) would have 128-192 MB and 4MCDwhile the RX7700XT I would only have 64 MB and monolithic design. With these specifications, AMD hopes to compete with the new generation of NVIDIA in 4nm paving the way for RDNA 4.
The goal could be an evolutionary design through a redesign (or refresh, as everyone wants) where the company could implement 3D V-Cover vertical in future RX 7000 GPUs or just leave it for the RX 8000, where in addition to cutting costs by maintaining a partially monolithic design with small, inexpensive-to-manufacture and scalable chips, the company can mold the architecture and l adapt to your needs, not depending so much on the bandwidth of GDDR6X memory, being able to opt for cheaper and slower modules without losing performance.
Navi 31 will therefore be a chiplet-based chip that could have a very interesting configuration moving away from AMD’s high-performance CDNA 2 architectures and opting for a more Ryzen “focus” with an I/O Die.
GOING THROUGH: Kopite7kimi