Early benchmarks of the upcoming Intel 12th gen Alder Lake Core i9-12900K in combination with AMD's just announced Radeon RX 6600 GPU were posted on Chinese social media. The results show good gains for the Core i9-12900K compared to the Ryzen 9 5900X, Ryzen 9 5950X, and the Core i9-11900K in 3DMark CPU tests. However, real-world gaming benchmarks do not seem to show very high differences, especially when paired with DDR4 RAM.
https://www.notebookcheck.net/Intel-Alder-Lake-Core-i9-12900K-shown-to-be-56-faster-than-AMD-Ryzen-9-5900X-in-Time-Spy-CPU-but-gaming-advantages-over-Ryzen-9-5950X-seem-miniscule-with-Radeon-RX-6600-and-DDR4-RAM.572802.0.html