alt Hacker NewsI do not know on what data you base your sentence "Intel's own Panther Lake CPU tile is on 18A and it's extremely disappointing in terms of perf/watt and raw perf."
Panther Lake does not have great raw performance, because for now Intel has not succeeded to obtain in their new 18A CMOS process clock frequencies as high as they get in the older TSMC 3-nm process used for their previous Arrow Lake H CPU generation and the CPU cores of Panther Lake have only minor changes that can affect performance in comparison with Arrow Lake/Lunar Lake.
On the other hand, from the published reviews that I have seen, Panther Lake has significantly better performance per watt than Arrow Lake H, which can be attributed only to the Intel 18A process when compared with the TSMC 3 nm process.
The energy efficiency i.e. performance per watt ratio of CPUs is mainly determined by the fabrication process and not by the CPU design, as long as the CPU designers are competent enough (unlike the single-thread performance, which is determined mainly by the CPU design).
So there is no doubt that Apple CPUs made with the Intel 18A process will have better performance per watt than those made with a TSMC 3-nm process. Moreover, because Apple CPUs can reach a given level of performance at lower clock frequencies, they should be much less affected by the lower clock frequencies attainable with Intel 18A than the Intel CPUs.
We also do not know whether Apple intends to use the Intel 18A process (currently used for Panther Lake laptop CPUs and Clearwater Forest server CPUs), or only its successor, Intel 14A.
All efficiency data can be found here: https://www.notebookcheck.net/Intel-Panther-Lake-Core-Ultra-...
The most important one for efficiency is ST perf/watt. MT perf/watt is largely based on how many cores there are. You can achieve better MT perf/watt simply by having more cores (more transistors) and run them at lower clocks. Panther Lake also has an entirely new MT config with 3 tiers of cores vs 2 for Arrow Lake.
For ST perf/watt, it loses to LNL.
Keep in mind that LNL and Arrow Lake used N3B, and future N3 nodes have been much more efficient. Panther Lake CPU is also a new design which should have improved perf/watt automatically regardless of node.
Based on this, one can deduce that Intel 18A is likely a bit worse than N3B and perhaps equivalent to N4P. Keep in mind that N3B went into production in late 2022 and N4P was a 2021 node.