016R35: There is no need to complicate your life with commands, just go to system settings (MSconfig) -> Boot -> Advanced Options -> And set the number of cores to a lower one, in my case I have a 32 core i9-13900k, I set it to 16 and the game works perfectly.
Please OP, if you read this, mark this post as the thread solution. It's the quickest and easiest, no need to complicate your life with commands or strange launch parameters.
JL: This is not an ideal solution, as you're effectively disabling several cores system wide just to play a single game, and would need to change the setting back and reboot if you want all your cores back.
DamIDhagor: Wow. I never received any Emails about replies to my thread. I just came across it after 3 years and I'm really happy that this post helped that many people!
JL: Thank you for this solution. It works great. I really wish CDPR would update/fix their game though.
Here is a permanent solution, i am using a 13900k, write in your desktop shortcut in target: C:\Windows\System32\cmd.exe /c start "launcher" /affinity 1 OR 0000FFFF (for 13900k users aka 15 cores) "Z:\Games\The Witcher 2 Enhanced Edition\Launcher.exe"
Basically cmd.exe /c start "program name(doesnt matter, you can name it like your exe's name)" /affinity 1 "program path(example like mine above)"
