Thought I would post the solution here. After checking everything over 2 weeks.
- Every fix you can find on the net (and the ones above)
- Tested different power supply
- Tested RAM
- Put in old 1060 3GB video card
- Changed CPU cooler from water to air
- Changed every GPU and CPU bios and OS setting
Finally - tried using a M.2 NVMe SSD instead of my Pioneer 1TB SDD - and the problem was solved. I dont know if it is the windows install or the drive itself. I beleive that some cheaper drivers poffload cache to the CPU as they dont have it onboard. We will never know.
Now with every in Call of Duty set at MAX the CPU doesnt even touch 60% - and the game is as smooth as silk.