Sorted, When I looked at the BIOS screen again, I noticed "F5 Restore to Previous Settings (or something similar"
I did this, checked with the photographs, restarted and everything is back to normal, apart from F1 at start up which will be another thread.
I think it was VoG who suggested taking photographs of the Bios screen, some time ago, what an excellent idea.
But... why would it be suggested, even on this site, to return to Default settings in the BIOS, what is the correct procedure for this??