For some reason, it has been like this for a while now, I have spots, black spots. Almost like pixels on planes and transparent surfaces.
I feel like have looked everywhere and can`t find out what I might have pressed or done (I have easy trigger fingers, they do what they want).
See attached photo, thanks 
Is this on one specific file OR all files? Can you check your graphic card and it's driver if they are OK? Finally can you check and see if you set the part display or appearance on this part or have the top face set to transparent?
Hi Thomas
Did you check these?
Also Real View
I have now, and now I remember why they where unchecked. Because my graphics card and processor fans goes bananas only when dealing with one simple part.
Is that the sequel to this?
Hi Thomas
Did you check these?
Also Real View