I lapped my processor caps to bare copper. I chose to use IC Diamond nano-diamond paste, which rated well. I sent my processors to Katy, Texas so that Silicon Lottery could de-lid and re-lid my SKY/KABY cpus with Thermal Grizzly Conductonaut. I just retired those processors in rebuilds, with a minor setback in a fresh installation of Windows 11 and prayerful reinstalls of licensed software.
I ended up with two identical 11th gen systems — one with IC Diamond and a Grand Macho RT cooler, and the other with Halnziye HY-P17. This latter you can read about; it’s a Chinese product, rumored to have counterfeits, but with reviews touting 17.3 W / m.K conductivity. Beyond 17.3 there might be only the 75 W/m.K for Conductonaut.
Two identical systems in the same room, one with IC Diamond the other with Halnziye, and running OCCT, XTU, Prime95…