Wolfstriked, that's an interesting Point. Believe it or not, but I was working today with exactly the same Problem...

This is what I've found out:

I have changed my Resolution in my NVIDIA Control-Panel, that was the only Way to change the Resolution in WOFF. Played with different Resolutions, but no Success.

After that, I changed the Refreshrate for my Monitor from 60 HZ down to 50 HZ.

That means, my FPS are now locked at 50.

I also changed the Pre-Rendered Frames from 1 up to 3, V-Sync is ON in Nvidia-Control Panel.

In Workshop Settings I have left everything as it is.

Believe it or not, but the Game runs very good now, not perfect at all, it surely needs some more Tweaks, but my Eyes were getting very big, when I saw the good Results.

I don't know how and I don't know why, but this whole Problem has something to do with my Graphics-Card and the NVIDIA-Driver. It's definetely NOT the CPU.

Some Guys might want to try this out, as always, I can not promise if this will help, but in my Case it made a Difference, though!