Viewport rendering Height with black patches?

[mattt47917771]

Hi Guys,
I'm hoping someone can help me with this issue I'm having?
Basically in the viewport hieght is giving me some odd black edges?  I'm guessing this is a veiwport only issue as all maps look ok to me.

Am I missing a setting, or something?
Any help greatly appreciated! 

Thanks,
Matt

[Ares Hovhannesyan]

Did you try to change Ambient Occlusion parameters? Also it can be amount of metallic to roughnes.