At stock multiplier settings, Fmax (or Frequency max) is the maximum clock speed that an AMD "Zen" CPU will automatically boost/overclock to. 

You'll need to increase the multiplier value and overclock manually to go above this. AMD's forthcoming flagship desktop CPU, the Ryzen 9 7950X "Zen 4," is said to have a Fmax of 5.85 GHz. You'll need to enable options like Precision Boost Overdrive (PBO) to eliminate the power limits required to get here.

Importantly, the F-max frequency for Ryzen 5000 series may still be tweaked via F-max Offset, implying that Ryzen 7000 series can still clock higher until AMD changes the underlying technology for Zen4 design. Angstronomics originally mentioned the F-max frequency of 5.85 GHz in May of this year. This frequency, however, was not associated with any SKU at the time.

AMD's Ryzen 9 7950X is a 16-core processor that uses the Zen4 microarchitecture. It is said to have two CCDs with 16 cores dubbed "Persephone." According to the leaker, the top CPU fight will be between the 7950X's 5.85 GHz and the i9-13900K, which will allegedly boost up to 5.8 GHz with Thermal Velocity Boost. In addition to those assertions, the leaker included a screenshot of the Ryzen 9 7950X CPU, which is not yet fully supported by the software. It indicates 16 cores with a core speed of 4848 MHz clock, but no indication of the workload. AVX512 support is also mentioned in the instructions.

AMD Ryzen 9 7950X Frequency could Peak at at 5.85 GHz