Well this is a weird one.
While back I read on ROG forums, one guys comments on OC'ing. "Your're overclocking now, sometimes you get to be Clint Eastwood or sometimes you get to be his dog" !!!.
I'll explain. For some reason early on in the OC I input 1.250_v in BIOS for v-core after a no start at 1.200v.
Quite quickly the OC becomes stable on R IV E Black Edition with XMP OC as on previous OC's the manual OC won't work on this board.
Then getting on with a stability test in P95 (or similar) I think to myself I can get the v-core down a fair bit more and get rid of some droop that caught me offguard which was as much as 0.075v so from 1.250v in BIOS it would droop to 1.168v at the lowest which I thought was the cause of a blue screen at 1.175v in BIOS which may have caused the v_core to go down to 1.125v or not far from that hence a crash on boot.
Anyway after attempting to alter load line calibration the system would not boot at all and trying to alter the previous 1.250v resulted in hours of wasted time and no result apart from 1.240v and no answer to the v-droop which also caused a v-rise on idle.
So after all this I just resulted to leaving the 1.250v although 1.240v did work. 1.230v did not boot even with LLC set to high.
The only parameter not altered was the v-core on boot in "digi-plus power" control which might have helped but maybe not on this board.
So the Xeon E5-2697_V2 seems pretty difficult to do much with !!! but 3.4 Ghz all core boost and a Passmark of 20,000 points seems to be a good result on this X79 platform and thankfully even though the 2697 v2 is a little pricey (£300) it's way under the initial asking price of $2,000 !!! so not too bad at all on R IV E !!!