The tip to switch off multiplayer helped a lot. I now have around 23 fps (at LOW settings)
I have yet to see what it will be like when I switch back to ultra. (what I was using before WU4)
Thnaks guys 
My specs:
Motherboard ASUS PRIME X399-A
AMD Ryzen Threadripper 2950X (16 cores)
NVIDIA GeForce GTX 1080 (latest drivers)
32Gb DDR4-2400 / PC4-19200 DDR4 SDRAM UDIMM
Monitor SAMSUNG SAM0E3C (4k, 3840x2160)