I think the buffer_storage isn't being enabled on GTX 780 cards because opengl now runs really slow without vertex streaming hack enabled. I'm not the only GTX 7XX user to have this issue, can someone look into this?
JMC47's had buffer_storage working fine on his GTX 760, from what I've heard. I think he said it was even slightly faster than with VSH.
I realize that this is rather unhelpful, but you may want to double-check that you're running the latest drivers – try installing the beta ones, maybe. Same for Dolphin, of course.