Mate if it crashes (obviously not due to porr programming) then obviously it is not 100% stable and if it was me i would not trust it. Also your voltages are going skyhigh. It is either a memory timing issue (not CPU bound), so try another way to overclock successfully, or that is your CPU's limit. For better or worse, you have to accept it and leave it at the maximum that you have it stable. Unless of course money is no issue for you, so go ahead and either burn it, or buy a new one and replace this.
When something starts to eat up lots of power for little extra gain, then it is not worth it in my oppinion.
Eg. My E8400 goes up to 4.05GHz at 1.43V, to go to 4.1GHz and more it needs 1.46V at least. No way i am willing to sacrifice 0.03V, and an increase of 5oC on my temperatures for 50MHz!