There’s no need to stick to an arbitrary number like 65w, change it at your will depending on your cooling or desired power consumption and the CPU will do the best it can with the given power budget.

No reason to worry about small difference to behaviour. The k just lets you overclock it. No reason to change anything let it be.

If you want the safest possible temps without performance loss, try to find the stable voltage offset of your cpu, then try to keep your core clocks near together until your cpu wont exceed more than 1.3 Volts

For example i found out my 11900k is stable on 49xGhz all cores with 1.22Volts, as im not worried about single core boosts up to 5.3Ghz, i cut them all to 49x, so even on single core tasks my cpu will stay at 1.22Volts.

I tried to do some benchmarks to make sure this single core underclock wont affect my gaming performance, and i couldnt believe my eyes that this thing i did actually increased my benchmark scores & got me better 1% lows.

By doing this, my cpu is now running 49x instead of 48x all core boost, but consuming 15% less power while stress test and 40% less power while gaming, intel stock setting was getting my cpu really hot on single core tasks with crazy 1.55Volts spikes.

Sorry for long reply