The voltage seems fine, how much thermal paste are you using? A pea sized amount is enough. Also show me a picture of your computer case (inside), also have you oriented the fans correctly? The top/rear fans should be exhausts while the side and front fans should be intakes.
Problem Solved!!!! Bought a cooler and now my idle is 37C and under load its mid 40s!!
I didn't think stock heat sinks could be so bad? or maybe it was just not seated correctly but hard to believe it would come undone after 3 years.
Plastic is a very high viscosity fluid. Give it some heat and pressure/tension for long enough, it will "flow" and it only needs to 'flow' by a few hundred micrometers to lose most of its contact force in the case of Intel's stock HSF.
My C2D-E8400's stock HSF also lasted for approximately three years before this happened, as did nearly everybody else I know who has owned one of Intel's plastic push-pin contraptions. It appears to be nearly systematic.