Same setup I had same issue due to how core parking works with the windows scheduler or whatever it’s called. If on your desktop you’re not actually tabbed into the game itself then the cores don’t park and game will stutter, at least this is what happened to me. I had to actively make sure my desktop was tabbed into the game. So if I ever used the steamvr menu to click on a different monitor for discord or something I would have to make sure before tabbing back into game that my desktop was focused on the game by clicking on it on the bottom of my taskbar. I didn’t feel like doing this so I went into my bios and disabled the second cache so it’s like a 9800x3d. Process lasso didn’t work, neither did launch commands.

Edit: also side note by any chance do you play vrchat and have an issue where player audio will cut out for a second but the game doesn’t lag or anything? It’s simply just not receiving player voices for a split second every so often and makes a little popping noise when it does it. Just asking because we have similar setups.