right-click in blank area of screen -> Update display ?
If that works, you might want to read the threads about the faceting that goes on...
Production: NX10.0.3.5 MP16/TC11.2
I'd rather be e-steamed than e-diseaseled
I was having this same issue - and it has bugged me for the last year or so. Especially, when I'm clipping though objects and trying to get screenshots for presentations...I came onto this community to ask for help, and stumbled across this post.
It got me thinking, and I tried a few things that resolved it.
If you go to Visualization, and Facet Settings (or just type Facet Settings in the Command Finder window)...Change the Facet Scale from Part to View.
That made the ghost lines disappear for me and I'm very happy now.