ok guys I just found out that when OV_CPU & OV_NB disabled system won't boot even with voltages below 1.7v like 1.33v for instance. Once changed to enabled able to oc again to 3.8ghz.
Well I guess I'm going to put more vcore then. Can anyone verify that load line calibration puts more voltage than needed? For example, I set vcore to 1.33v with load line calibration I get 1.35v