Images and the specifications of the XFX Radeon RX 590 Fatboy graphics card have been posted online. The card is obviously based on the upcoming RX 590 that features the Polaris 30 graphics processing unit based on the 12 nm FinFET process. The Fatboy variant will offer a boost clock of 1600 MHz and have a 256-bit memory bus.
https://www.notebookcheck.net/XFX-Radeon-RX-590-Fatboy-graphics-card-details-revealed.361121.0.html