update - it does not happen with designer pro 18 on my laptop, which has different graphics: nvidia GeForce RTX 2060

the GeForce GTX 1070 on the desktop is over 6 years old, the oldest hardware component in the machine as it happens, been lots of changes to windows if not xara since then

to be sure I'd have to install ver19/20 on laptop, yet more round tuit....

thanks again for the help