Band of realy bad jaggies

[69th_Panp]

Anyone one know what is causing this ?

It comes and goes, will be there one mission and wont be the next one .

Its Driving me nuts 

system spec

windows 10 pro

3440x 1440

GTX 1080ti hybred / driver 398.86

4790 K at 4000

water cooled 

I've uninstalled drivers 

changed drivers 

changed from window mode to full screen

always right there in the middle of the screen, big chunk of jaggies

 

[Ehret]

Not sure for 100% but clouds rendering is done using something resembling voxels which aren't small enough. Thus, in some places they can be visible as block artifacts.