I've owned 5 bloomfield chips. Two 930's and three 950's. My 3x4GB Mushkin 2000MHz 10-10-10-27 kit needed 1.4875v QPI to run on the best of those chips. On the worst it needed 1.56v.

I got a 970 from retailedge and it only needs 1.3375v QPI for the same kit at 2000MHz 9-9-9-25.

Do we have any idea what's new in 1207 that 'improves system stability' ?