The 6800/6900 series will not (yet) replace the Navi lineup; it's a different product category as AMD did not have an enthusiast-class performing product that matched NVIDIA's performance in the enthusiast spectrum. The Radeon RX 6900 XT has 5120 stream/Shader processors active, the 6800 3840 units. This card indeed registers back to us with a 2340 MHz max Turbo clock. The BIOS offers fan stop in idle, meaning the card is passive (not fans spinning) when not utilized, and that brings you the fortunate effect of a completely silent product. The card measures up to 32cm in length and 14cm in height.
The card has dual BIOS, the OC mode is preferred and already os really silent by itself whilst offering proper cooling temperatures.