650 is NG
looking at the referenced link .... nVidia's minimum is 675 (so say 750) ..... Guru 3D has 800 but, as explained on the linked page, that's a bit over sated as they have an extra 100 watts being pulled by the 3960K (230 watts) as opposed to haswell (130 w. OC) ... you'd want 800 w/ a 3960c oc'd as theirs is (230 watts)