1.4v is Vabsolute, 1.52v is max SVID just like SB. Max VTT and VCCSA is 1.4v. Those are absolute ratings listed, but intel lowered max vcore from 1.52v for SB to 1.4v for SBe. IMo don't go over 1.7v, i wouldn't even go over 1.6v at least above ambient. They are all in the datasheet, check em out under electrical specifications.