Black stripe trough screen ue4?

I have Always this black stripe troughout my screen, only in the editor and also ingame, not in other programms. In some parts of the editor it does not happen. Only on trees and objects it seems. I have the following pc:

I74970K, GTX970, 8gig ram, windows 10. plus the newest ue4: 4.7.6. in the earlier version it also gave this black line.

see image here:

What is the reasson behind these black lines? Somehow the ue4 editor does not work perfect with my new hardware?

Im having the problem as well

I had the same issue turn up or down the fog inscattering color in your exponetial height fog. Or turn down your fog density