I managed to put 5800x with Asetek and used liquid metal (grizzly condactonaut). In OCCT it reached max 93C. I set it to 4500 Mhz and 1.25V in Bios and it goes up to 90 max. I will run Cinebench later to see what is the performance degradation and will post results here (provided that I will get my Dan back which got lost with my luggage at the airport :-)
The issue will be more present with faster memory like 4000MHz, because the "Infinity fabric" will put a serious toll on your FCLK voltage