I have some information regard Mac Pro.
- They have try to push M2 Ultra P-core to run around 4.2 GHz
- it success, but with much more power consumption.
- Mac Pro thermal heatsink can be easily handle that heat outputs.
- Doesn't decided that how the final spec will be.
Based on Primate's GB6 benchmark for the M2 Max MBP (3.66 GHz), 4.2 GHz should give a GB6 single-core score of:
2747 * 4.2/3.66 = 3152
This would be 3152/3044 = 3.5% faster than the fastest processor listed on Primate's site (i9-13900KS, which is a 6.0 GHz/328 W special gaming edition of the i9-13900K, and Intel's fastest SC CPU), and 3152/2935 = 7% faster than the i9-13900K. [For single-core performance.]
It would make sense for Apple to target 4.2 GHz, since that would enable them to boast the MP has the fastest SC performance of any production CPU (i.e., one not subsequently overclocked).
Further, if this CPU can maintain a good fraction of its SC clock speed when all cores are active, it could post a truly impressive MC score, exceeding any consumer processor available today, and also providing competition to what will probably be the fastest (for MC) workstation CPU, the upcoming 56-core Sapphire Rapids Xeon (while trouncing that in SC performance, since the Xeons always sacrifice SC for MC).