I looked over a Tom's Hardware test of that CPU and while it does seem to run rather hot for an Intel CPU, it still shouldn't hit 80. Have you got that new cooler and case yet? If so, and it's still running around 70 degrees, make sure you applied the thermal paste correctly; if not, it should get even cooler once you get those, possibly even to the point where you could return the voltage to normal levels without worrying.