Thx for the replies. Before I had an AIO I was using an air cooler (but without a contact frame) and it was exactly the same behavior, and the mount was good, I checked it couple of times. The thermal paste application should also be ok (if anything, I put too much maybe..but no way too little, it was an "X" pattern)
Maybe the Arctic contact frame is not as good as the other brands, but it should be a bit better than the stock ILM.
Now to be more precise, the P-cores that reach the 80+c, they are not all the time at 80, they are in the range of 70c - 80c, but some P-cores are at ~60c and not usually go up too much.. So some of the P-cores are certainly cooler than others.
I also get big jumps sometimes at idle, it usually at 29-30c at the package and than I open some program or something it can jump to 60 instantly.. I assume this is normal but I am not sure. And those are probably those "hotter" P -core that have those jumps.
Do any of you experience the same CPU core temps behavior?
EDIT: it seems that P-cores 0-3 are the colder ones, and P-cores 4-6 are the ones that getting hot (also the only ones that go up to 6ghz) and the E-cores are all close to each other in temperature.