Radeon Pro Vega II Duo MPX Module

The Radeon Pro Vega II Duo is a dual GPU that was developed by AMD as an optional MPX module for the 3rd-generation Mac Pro. Up to two can be installed at a time (for a total of four GPUs) and it supports Infinity Fabric Link to increase the speed of inter-GPU data transmission by up to five-fold.

Description
The Radeon Pro Vega II Duo MPX Module is based on two of AMD's high-end Vega 20 workstation graphics chips that were built on the 7 nm process. The GPU clock speed was 1.4 GHz, which could be boosted to 1.72 GHz, producing up to a total of 28.3 teraflops. It contained 32 GB of video RAM for each GPU, running at 1 GHz. It features one HDMI 2.0 port and four USB-C compatible Thunderbolt 3 ports. It could support four 5K or 6K displays, or eight 4K displays. The first Thunderbolt 3 port and the HDMI 2.0 port shared a PCIe lane, reducing the output of that Thunderbolt 3 port if the HDMI port was used. The MPX module took up the space of two double-wide PCIe cards, but did not require an auxiliary power cable as it could draw all necessary power from the proprietary MPX connector.

Successor
On August 3, 2021, Apple began offering the Radeon Pro W6800X Duo MPX Module as a higher-performance option, though the Radeon Pro Vega II Duo remained on sale for existing users who wished to add a second matching module.