AMD RDNA 3 Flagship GPU, Navi 31 “Plum Bonito” Leaks Out Ahead of Today’s Radeon RX 7900 Series Unveil
The first picture of the AMD Navi 31 GPU die that will go on to power the flagship Radeon RX 7000 series graphics cards such as the RX 7900 XTX & RX 7900 XT has leaked out and gives us a glimpse of what to expect at tonight’s unveil. The picture confirms the use of 6 chiplets surrounding the main GPU die. These might resemble the HBM modules but they don’t feature any VRAM support. The chiplets are expected to house the memory controllers and the Infinity Cache (LLC) pool.
AMD Navi 31 “Plum Bonito” GPU Configuration
The AMD Navi 31 GPU, the flagship RDNA 3 chip, would power the next-gen enthusiast cards such as the Radeon RX 7900 XTX/XT graphics card. We have heard that AMD will drop CU (Compute Units) in favor of WGP (Work Group Processors) on its next-gen RDNA 3 GPUs. Each WGP will house dual CU (Compute Units) but with twice the SIMD32 clusters as opposed to just 2 on each CU within RDNA 2. Rumors are that AMD has the option to select between Samsung and TSMC for the 6nm die.
AMD Navi 31: 12288 Cores, 384-bit Bus, 192 MB Infinity Cache, 308mm2 GPU Die @5nm AMD Navi 21: 5120 Cores, 384-bit Bus, 128 MB Infinity Cache, 520mm2 GPU Die @7nm
According to the latest information, the AMD Navi 31 GPU with RDNA 3 architecture is expected to offer a single GCD with 48 WGPs, 12 SAs, and 6 SEs. This will give out a total of 12,288 SPs or stream processors. This is an increase of 2.4x in cores compared to the 5120 SPs featured on the Navi 21 GPU. The GPU or the Navi 31 GCD is said to measure 308mm2 and will come packaged on TSMC’s 5nm process node. The cut-down variant will feature 42 WGPs or 10,752 cores and 5 MCDs for 80MB Infinity Cache across a 320-bit bus interface. The Navi 31 GPU will also carry 6 MCD’s which will feature 16 MB Infinity Cache per die and are also likely to carry the 64-bit (32-bit x 2) memory controllers that will provide the chip with a 384-bit bus interface. While this equals 96 MB of Infinity Cache which is lower than the 128 MB featured on the current Navi 21 GPUs, there’s also a 3D-Stacked solution in the works which was pointed out recently and that would double the Infinity Cache with 32 MB (16 MB 0-hi + 16 MB 1-hi) capacities for a total of 192 MB of cache. This is a 50% increase versus the current Navi 21 design and it also makes Navi 31 the first GPU with both, chiplet and 3D stacked designs. These chiplets or MCD’s will be fabricated on TSMC’s 6nm process node and measure 37.5mm2 each. The initial lineup is expected to include two cards based on the flagship Navi 31 GPU, the Radeon RX 7900 XTX 24 GB & the Radeon RX 7900 XT 20 GB. AMD will be unveiling its RDNA 3 GPU architecture and the Radeon RX 7000 graphics cards in a few hours while the actual retail launch will take place a few weeks later.