AMD Instinct MI300 GPUs rumored to feature 3D die-stacking, up to eight Compute Dies, support for HBM3 and PCIe Gen5

Please note that this post is tagged as a rumor .

AMD MI300 with up to 5nm Compute Dies

We are still in the early stage of next-gen AMD Instinct MI300 rumors, however Moore’s Law is Dead claims to have actual photos that were used to create the following renders of said GPUs.

Just as the MI200, the MI300 is a family of data-center GPUs. Therefore, one cannot say that MI300 has one set of specifications. On the contrary, the MI300 will be available in many formats, featuring from two to eight HBM3 memory stacks. Furthermore, the MI300 will feature 3D stacking with I/O (or base) chiplet right under the new compute dies.

AMD MI300 GPU Family Render, Source: Moore’s Law is Dead

Here, one should note that Compute dies for MI300 will not supposedly feature a single type of IP block, but rather give customers some options to choose from. Under each 5nm Compute die, there is an I/O die. This base tile which is manufactured using 6 nm process is attached to two stacks of HBM3 memory. This would be the first time AMD is using 3D stacked dies.

In terms of power, each Compute die may consume around 150 Watts. So the top configuration could consume more than 600W, which shouldn’t really be that surprising considering MI250X already has 560W TDP spec for the OAM form factor.

AMD MI300 GPU Rumors, Source: Moore’s Law is Dead

Each Compute Die should measure around 110 mm², while the interposer for the biggest variant would be as big as 2750 mm². These Compute dies would also have around 20,000 connections with each other, which is a double of what Apple offers for its M1 Ultra silicon compute chiplets.

The release date of Instinct MI300 is currently unknown, but there is a good reason to believe that by the time MI300 is released, NVIDIA Hopper and Intel Ponte Vecchio should already be available on the market.

RUMORED AMD Instinct Accelerators Specifications
VideoCardzAMD Radeon Instinct MI60AMD Instinct MI100AMD Instinct MI250XAMD Instinct MI300 (flagship)
Architecture & Nodes7nm GCN5 (GFX906)7nm CDNA1 (GFX908)6nm CDNA2 (GFX90A) 5nm CDNA3 (GFX940) +
6nm (base)
GPUVega 20ArcturusAldebaran (MCM) ? (3D Die Stacking)
Base Chiplets 2
Compute Tiles112 8
Compute Units64120220 TBC
GPU Clock Speed1800 MHz~1500 MHz~1700 MHz TBC
FP16 Compute29.5 TFLOPS185 TFLOPS383 TFLOPS TBC
FP32 Compute14.7 TFLOPS23.1 TFLOPS47.9 TFLOPS TBC
FP64 Compute7.4 TFLOPS11.5 TFLOPS47.9 TFLOPS TBC
VRAM32 GB HBM232 GB HBM2128 GB
8x HBM2e
8x HBM3 stack
Memory Clock2.0 Gbps2.4 Gbps3.2 Gbps TBC
Memory Bus4096-bit4096-bit8192-bit 8192-bit
Memory Bandwidth1 TB/s1.23 TB/s3.2 TB/s TBC
Form FactorDual Slot, Full LengthDual Slot, Full LengthOAM OAM
TDP300W300W560W 600W+

Source:

The following video is timestamped
[Moore's Law Is Dead] AMD Navi 31 & MI300 Leak: 3D Stacking the Deck against Lovelace & Hopper (26,749 views)