You didn't mention, that you were talking about an undervolted ADL and HT was off.
My fault, sorry if that made an impression that out of box 12900K can somehow hit 5Ghz on P cores on such low power.
That is simply not happening cause Intel was not caring about efficiency at those operating points for this SKU.
During manufacture of chip several things happen that ruin any illusion of operating properly at lowest possible power at any given point:
1) Each core is characterized and has it's v/f curve determined. So in our 5Ghz case what matters is last three points. 42x, 48x and 53x ( later mfg date 12900K will have 52x instead of 53x as so called "OC ratio" ).
2) Each cores values are written to chip and are then used to interpolate voltage required at any given operational point.
During operation, largest requested value is selected out of active cores, so if a chip has a lemon core that cannot do 53x without 0.05V more than best core ( but would work perfectly @ 5ghz at same low voltage as others) => bad for you.
So at any point other than 48x or 53x we are at huge disadvantage already and 50x is esp hurt since it is far away from 53x, and yet quality of chip at peak frequency determined how much power it will eat at lower freq.
Later on after this voltage is decided by interpolation @50x, the usual guard bands for AVX, for motherboard VRM quality and so on are added and we arrive at ridiculous voltage that has nothing to do what this particular chip would really need on this frequency. Then feedback loop of TVB happens where chips voltage gets corrected by raising temperature to keep it stable.
Power usage goes ballistic, freq is dropped, but temps are stuck high, so is TVB correction, further inefficient points are selected and chip will eventually settle down on
48-49 if load is low enough or drop down to
42-43 if it is brutal as shown by ComputerBase in Your article.
Back to our original discussion -> 5ghz is just a point I happen to be running, it is in no way in most efficient part of operation for GC core in 4-5ghz range. But ballpark figure is that Intel would need ~15W @ 5Ghz to run CB23 for GC cores and we will see how much AMD will need. I am running 5950x 4.4ghz in low 1.1x regime, so we'll see how 7950x will do.
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