https://www.theverge.com/2018/11/14/18093628/apple-macbook-pro-amd-radeon-pro-vega-20-16-gpu-options-buy

As promised, Apple has updated its MacBook Pro configurations with new options for AMD Radeon Pro Vega graphics cards, specifically the all-new Pro Vega 16 and Pro Vega 20 options. Apple first announced these new component choices as part of its fall Mac hardware event, where it announced a new MacBook Air and Mac mini.

The options are now available on Apple’s online store for the 15-inch MacBook Pro with Touch Bar. It’s only available on the laptop’s highest-end configuration. You’ll be paying an extra $250 for the Pro Vega 16, and an extra $350 for the Pro Vega 20. That’s on top of the laptop’s $2,799 base cost. However, the laptop’s base GPU is seeing a small update from the Radeon Pro 555X to the 560X, which was previously an upgrade.