I have the same problem with my Ryzen 2600 and the answer is actually easy, KCD is optimized to use 8 cores for it’s “optimization”, and since there is no specific code to take advantage of SMT in case of more threads, the Ryzen cores are being divided in 2, but it’s no real SMT usage, it’s just cores that are dividing the workload on their virtual threads, without proper usage for it.
Don’t think it degrades performance however, it doesn’t, but it doesn’t improve it either. At this point only 2 things can be done, either get a better CPU when a better CPU is available (still 8 core, but better IPC and faster clocks, maybe higher cache can help ? I’ll get back to you as soon as I get my hands on the 3800X haha), and/or porting the game on CryEngine 5, which has a much more intelligent multithreading system apparently, and also has DX12, which could improve performance on modern hardware because the game is super heavy in drawcalls, and also allow the use of RayTracing capabilities.
EDIT : wait hold it ! Apparently those improvements will come in CryEngine 5.7 coming next year, so… yep it’s a dead end since then.
Please Warhorse, port the game on CryEngine 5 and release a super royal edition for next gen consoles and PC as a free upgrade (after mod support of course), I don’t mind if I have to wait 3 years for it haha