Since I had to build a new PC recently the screen didn`t look right but I couldn`t identify just why this was.
This morning though while re installing Google Photos Screensaver,now part of Picassa not a stand alone as it used to be,I realised that the screen res was set way to low from the 1440x900 it should be.

It`s made a huge difference to the appearance.It now looks as good as formerly.I don`t know why I didn`t think of it before