AMD Instinct MI450 Accelerators Allegedly Feature Brand New XSwitch Interconnect

AMD's next-gen HPC accelerator, the Instinct MI450, is allegedly going to utilize a brand-new interconnect fabric.

An internal email shared by HXL (@9550Pro) reveals that AMD might soon begin talking about its next-gen HPC accelerators. Although the company has yet to launch its Instinct MI300 APUs which are scheduled for arrival later this year, the Instinct MI400 series is already being planned and will be powering next-gen data center and cloud platforms in the years ahead.

As per the email, there are a total of three new products discussed which include Weisshorn, MI450 and XSwitch (and beyond). Kepler_L2 reveals that Weisshorn is the codename for AMD Venice CPUs which will utilize the Zen 6 "Morpheus" architecture and be featured within the EPYC lineup. These chips are expected around 2025-2026.

Weisshorn is Venice.

— Kepler (@Kepler_L2) May 25, 2023

As for the AMD Instinct MI450, it will be part of the MI400 family that utilizes a future CDNA GPU architecture along with a combination of x86 CPU architectures.

Considering how heavy AMD is going down the chiplet route, they will likely include multiple types of the same cores across the next-generation APUs which means that the Instinct MI300 is just a taste of what to expect from team red. Possible codenames have also been revealed by Kepler_L2 which point out to Mercury, Venus, and Earth. AMD has previously used stars as internal naming conventions for its GPUs.

Few more codenames ????

Navi4XNavi4MNavi4C

MI400 Mercury/Venus/Earth

— Kepler (@Kepler_L2) April 18, 2023

The AMD Instinct MI100 series was labeled as "Arcturus" while the MI200 series was labeled as "Aldebaran". In addition to these, AMD is also expected to introduce a brand new interconnect known as XSwitch which is likely going to be a main competitor against NVLINK from NVIDIA. The details remain unknown but HXL shared a picture that shows the topology of the MI300 node.

A total of four Instinct MI300 APUs are connected together via 6 infinity fabric interconnects & since the CPU is directly onboard the main APU interposer, you can have a fast on-die interconnect close to the GPU cores. This isn't the XSwitch interconnect though and that might be vastly different if AMD is completely doing work from the ground up. AMD has so far confirmed that the MI400 HPC APU is part of the Instinct roadmap and it should be a very powerful chip that propels AMD in the AI era.