Hi Tony thanks for the response.
I have (just) cracked the problem - it is an option in the ATI Catalyst setting "Video Demo Mode" - there is a box called "Enable Demo Mode" - I had inadvertently ticked that AND the next box called "Split Screen Mode". Once I cleared these - everything was fine - so many facilities!
Regarding Splash - yes it is marvellous, James put me on to it and there is a new release 1.0.4 which solves some sillies - Mirillis are very good and thier support is highly responsive.
Don
Gigabyte I7/4940 O/C 4.3, Noctua Cooler 10GB DDR3, 4 x 1TB, 1TB SSD, Geoforce GTX660 TI 8500W PSU, Windows 10 Pro 64bit.