well what I did to fix the problem was go to http://www.nvidia.co.uk/Download/Find.aspx?lang=en-uk and select your graphics card..make sure u download the "GeForce/ION Release 190" release (think it was 190.62 which was the last one that worked for me), then restart pc and it should work.
but i dunno why it works for 1.51 and not 1.41 so it's probably something else.