No different with a re-install so went to the Nvidea website and downloaded again. The original Beta I downloaded was 160Mb and this new one is 201Mb and after installing this one the option to 'change screen res' is now listed.
Apart from the file size, the only other difference is one has 'English' in the file name and the new one has 'International'. May be it was a duff file/download?
