I can’t seem to get rid of the blue background as shown in the attached image. I’m in wireframe mode but this only shows up in the perspective and right views. It is correct in the top and front view.
Thanks,
Dennis
Does this happen with all display modes? If so, might you have accidentally set GradientView in those two viewports? It doesn’t look very gradient, but maybe… With the viewport active, type the command and see if it goes away… Its a toggle.
–Mitch
That wasn’t it, but since my post the problem is now only in the front view. Hmm…
Bluescreen!! 
Hmm, might be a video glitch, I might try just restarting Rhino…
–Mitch
Must have been. The problem went away. Should have opted for the Quadro instead of the GeForce I think!