Juli Clover, MacRumors:

Starting today, customers who purchase a Mac Pro can choose to add a Radeon Pro W5700X graphics card with 16GB of GDDR6 memory to their machines when using Apple’s build-to-order feature, a new option that was just added.

The card can be added to a custom machine for $600, while a dual-GPU option is $1,600. The single GPU option can be ordered on the Apple Store here for $1,000.