[ksec]

If you plug some numbers in, In terms of Pref / Watt M2 is still ahead. But 7840U has closed the gap.

[okamiueru]

Does this mean that the Perf/Watt of the M2 Max 12 Core is almost half that of the Ryzen 9 7945HX?

I think it's impressive to not only double the performance, and still keep roughly the same power rating.