https://wccftech.com/amd-radeon-rx-6900-xt-flagship-big-navi-graphics-card-unveiled-999-us-rtx-3090-competitor/

AMD has officially announced the fastest Radeon RX 6000 series graphics card, its Big Navi Radeon RX 6900 XT, which is designed to compete against NVIDIA's flagship, the GeForce RTX 3090 graphics card. The AMD Radeon RX 6900 XT with the RDNA 2 architecture delivers an insane improvement in performance per watt compared to AMD's last-generation RDNA 1 graphics architecture & trades blows with the top Ampere graphics cards at 4K resolution.

AMD's Radeon RX 6900 XT graphics card is based on the same RDNA 2 GPU architecture that is powering the rest of the Radeon RX 6000 series lineup. The main difference is that the GPU AMD decided to feature on its Radeon RX 6900 XT is the fully enabled variant of the fastest chip they have ever designed for the gaming segment and hence known as "Big Navi". It's the biggest gaming chip AMD has ever made on the FinFET 7nm process node and features an upgraded architecture which carries much higher efficiency and performance per watt.