Radeon Pro W6600X MPX Module

The Radeon Pro W6600X is a 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, but it does not support Infinity Fabric Link.

Description
The Radeon Pro W6600X MPX Module is based on AMD's high-end Navi 23 workstation graphics chip that was fabricated on the 7 nm process. The GPU can produce up to 9.8 teraflops and included 8 GB of GDDR6 video RAM. The module features two HDMI ports and communicates with the Mac Pro's built-in Thunderbolt 3 ports through the proprietary MPX connector. It could support two 5K or 6K displays, or four 4K displays. The MPX module took up the space of a double-wide PCIe card, but did not require an auxiliary power cable as it could draw all necessary power from the MPX connector.

Release
On March 8, 2022, Apple began offering the Radeon Pro W6600X as the new entry level model of the W6x00 series, and a higher-performance alternative to the default Radeon Pro W5500X MPX Module in a similar form factor.