I were updated BIOS to 1.5 with ME, changed CPU, PSU - same trouble.
My submittions on that CPU with other mobo:
http://hwbot.org/submission/2419274_johnw_xtu_core_i7_4770k_1343_marks
http://hwbot.org/submission/2419292_johnw_cinebench_r11.5_core_i7_4770k_12.82_points
http://hwbot.org/submission/2419285_johnw_3dmark06_geforce_gtx_770_47339_marks & etc
Not with CPU, because via M6E it's doesn't shuts down after 1.55 volts on VCore like it does on MPower. May be, in lastest beta MSI fixed that bug already.
But sample is bad, because only 5.9 valid - it is a little bit offtop).
So, I just tested my haswell on M6E, everithing is ok, but CPU is bad (5.9 @ 1.8 2c|2t, retail).
I posted link to lastest MPOwer beta bios, but didn't tryed it yet.Here is it http://forum.hwbot.org/showpost.php?p=262128&postcount=201
Didn't tryed with other CPU, but will test that CPU on other mobo very soon.
if vcore only is causing issue - yes.
if vccin only is causing issue - no.
Yes, It is CoolerMaster Silent Pro 800W Gold. Tryed to use Thotech Thunderbolt 850W - same. Next week will try to use Maximus 6 Extreme with that CPU, will see.