Because i cant download no more driver with windows 7.
If your hardware worked with 7 then it still works with 7. I can still download nvidia drivers for XP.
Personally I would stick with 7, but if you want to use 10 then you will have to go to the Roland site and hope they have drivers for your sound card that support 10.
NVidia are very good with backwards compatability support. IDK about Roland - if your sound card is an older model, maybe they will have updated drivers or maybe they wont.