Apple has been using dual Radeon GPU graphics cards in its highest-end Mac Pro systems for a couple of years now, with the latest AMD Radeon PRO W6800X Duo graphics card now benchmarked and man, is it an utter compute beast.
First off, the AMD Radeon PRO W6800W Duo graphics card features 2 x Navi 21 GPUs each with 60 compute units and 3840 stream processors. Each GPU has 32GB of GDDR6 memory for a total of 64GB of GDDR6 memory with 512GB/sec of memory bandwidth.
There's 30.2 TFLOPs of single-precision compute performance, and a whopping 60.4 TFLOPs of half-precision compute performance. There's an onboard Infinity Fabric Link connection that connects the 2 x W6800X GPUs together, pumping 84GB/sec in each direction. Then there's an external Infinity Fabric Link connection that enables 2 x W6800X Duo modules to connect 4 x W6800X GPUs.
- Two W6800X GPUs, each with 60 compute units and 3840 stream processors
- 64GB of GDDR6 memory (32GB per GPU), each with 512GB/s memory bandwidth
- Up to 30.2 teraflops single precision or 60.4 teraflops half precision
- Four Thunderbolt 3 ports and one HDMI 2.0 port on card
- Four DisplayPort connections routed to the system to support internal Thunderbolt 3 ports
- Support for up to eight 4K displays, four 5K displays, or six Pro Display XDRs
- Full-height MPX Module fills an MPX bay and uses extra power and PCIe bandwidth
- Onboard Infinity Fabric Link connection connects two W6800X GPUs at up to 84GB/s in each direction; external Infinity Fabric Link connection enables two W6800X Duo modules to connect four W6800X GPUs
The AMD Radeon PRO W6800X Duo GPU is used exclusively inside of Apple's new Mac Pro, offering its 64GB of GDDR6 memory and dual Navi 21 GPUs for a total of 120 compute units and 7680 stream processors. The GPU clocks of each GPU sit at 1979MHz, with 1TB/sec of memory bandwidth from the 64GB of GDDR6 RAM, on a 256-bit memory bus.
The card was run on the Octane benchmark and beats the pants off of everything. NVIDIA's very fastest workstation card is the RTX A6000, and it finishes the Octane benchmark in 16 seconds -- the new AMD Radeon PRO W6800X Duo graphics card finishes it in 14 seconds. You can also see the AMD Radeon PRO Vega II Duo, which is another dual-GPU card (on the Vega architecture, obviously) which was also another Apple Mac Pro exclusive graphics card.
There are a heap of other benchmarks that BareFeats ran, you can check them all out here.