https://www.techpowerup.com/307679/amd-ryzen-9-7950x-passively-cooled-with-copper-blocks A Reddit user has shared their experience of passively cooling an AMD Ryzen 9 7950X, with some modifications to the setup. Using the Streacom DB4 passively cooled case, the user u/AromaticImpress7778 pulled off cooling a processor with 16 cores and 32 threads with a TDP of 170 Watts. Interestingly, the Streacom DB4 case rates CPU support for only 65 Watts, meaning some modifications were in place. To support the high-TDP CPU, the user used two of the one-kilogram copper bars and attached them to the case. Heat is transferred to the two one-kilogram blocks using the case's default plate and an additional 233-gram copper plate for the CPU and motherboard. These big copper blocks are not soldered to the case, but instead, the user puts Thermal Grizzly Conductonaut liquid metal between copper parts and Arctic MX-6 between the case and copper.
To cool the AMD Ryzen 9 7950X and MSI B650I board, accompanied by HDPlex GaN 250 W and 64 GB of memory, the system did well enough for a passive build. After running the system at full load, the CPU reached 95 degrees Celsius for CCD1 and 95 degrees Celsius for CCD2. The external panels of the Streacom DB4 case were getting 50C to 60C of heat. Additionally, the user noted that the usage of this system will be more relaxed, as it will not run under full load for a prolonged period. Regarding the system's total weight, the entire build weighs around 13 KG, with 4.4 KG of that being only copper. The case weighs 7.5 KG, and the other parts weigh about one kilogram.
Personally I find the temps under load conditions too high for passive cooling.
