wing tip vprtices becoming black again

Hi everyone,

new computer, same problems -_- I installed the NGX on my new pc and after a while I have sgain black, fluffy, wingtip vortex, yesterday everything was ok and today the problem appeared, I tried the nvidia inspector following the guide on the forum, but i disabled it because I didn't like. here is what I have

and in this video from 1:37 is what I would like to get http://www.youtube.com/watch?v=rvh2k_4hG18 , could you kindly post your own photos for a comparison?

thank you very much