There isn’t a Windows sub-forum in the Software forum for some reason?
Anyway, this is odd. Every now and then some letters disappear from some parts of the screen:
Examples:
I have seen this occasionally.
I think this has come up before, something to do with the graphics card running out of memory?
Graphics card or driver problem. Seen it on other software for many different versions of Windows.
Somehow I doubt it. No problems editing videos with Magix for example. And my graphics card has plenty:
Randomly dropping bits of the display has been a graphics (card, memory, driver, OS) symptom for generations of Windows. It doesn’t mean the card is at fault, broken or doesn’t have enough memory, more like one part in that chain from App to Hardware has mapped a bit of memory wrong and hence the odd display.
They can be a bugger to diagnose as there are so many layers to wade through.
Thanks for the explanation ged. I have had a Windows PC for longer that I care to remember but I have never seen this before. But stranger things happen… 
Intel HD drivers strike again maybe…
30 years of working in IT and 10 years at Microsoft have made me see a boat load of weird things that windows can get up to.