I've seen different VID values in different threads in here. For example, see this thread. Of the people posting screenshots of their new G0 stepping Q6600s, I have seen several that show a VID of 1.2750v and one with a VID of 1.2625v. My B3 Q6600 gives a VID of 1.2875v.

1) What is the VID value?
2) Is it dynamic or fixed?
3) How does one change it?