Many thanks for that will give it a try. In the time you replied I have downloaded the latest Nvidia drivers which I hadn't thought to do given I wasn't having a problem with the Huey. This time I went for a Custom install instead of Express and that gave me the option to delete all the old installation rather than just update. That seemed to have made a difference when I went back into DCS and I didn't see the stuttering but need to experiment with it a bit more to see if that might have made the issue worse. In the meantime I'll try lowering the textures as you suggested and build up as I had everything set right on Max. Many thanks again !
"...to see if that might have made the issue worse." Meant to say "if that may have fixed the problem for me".