Looks like AMD will follow a launch order similar to Zen 3 with Zen 4 on the client platform as well. According to Greymon55 (a well-reputed tipster), the chipmaker will be launching the Ryzen 9 7950X, 7900X, Ryzen 7 7800X, and the Ryzen 5 7600X in September, delaying the Ryzen 7 7700X to mid or late 2023. The same goes for the non-X variants of the 7600X and the 7900X.
This, once again, boils down to profit margins. The higher-end SKUs such as the Ryzen 9 7900X and the 7800X, although featuring roughly he same specs as the 7900 and the 7700X, respectively cost notably more. And that means higher profits for AMD and its partners. Dr. Lisa Su has repeatedly reiterated that her company will be focusing on higher-end products with wider profit margins to improve returns. This is just the result of that statement.
Zen 4 should see roughly the same levels of performance gains as its predecessor. With an IPC boost of 8-10% and frequency gains of 400-500 MHz, you can easily expect single-threaded improvements of up to 20% and multi-threaded uplifts of up to 40-45%. The core counts will remain unchanged this generation. The Ryzen 9 7950X will pack 16 cores, 7900X with 12 cores, 7800X with 8 cores, and the 7600X with 6 cores. In contrast, Intel will be increasing the core counts on its 13th Gen Raptor Lake processors to 24. The efficiency cores will be bumped up to 16 on the Core i9-13900K, and 8 on the Core i7-13700K. How these chips will be priced, will ultimately deteremine their relevancy in the market.