https://www.youtube.com/v/F_2-yLm-4Sk&t=195sCyberpunk news just keeps getting "better".
Due to what is presumed to be an oversight when compiling the game, the executable doesn't recognize logical cores on AMD CPUs. This can be fixed by using a hex editor to change the .exe file.
Search for: 75 30 33 C9 B8 01 00 00 00 0F A2 8B C8 C1 F9 08
Change to: EB 30 33 C9 B8 01 00 00 00 0F A2 8B C8 C1 F9 08
This works for ver 1.04. CDPR hasn't acknowledged this yet, but I can't believe they haven't heard about it by now. Presumably it will be fixed by 1.05.
I have a Ryzen 5 3600 and I can personally confirm that this does work.