A good reason that you are requiring more Vcore is because when you first got it you leaned on the voltage too much....Possibly! I find since back with 939 Opterons and x2 overclocking is that with AMD Processors its Taboo to intruce High Voltage to the Processor off the front line I also find that if you start out with lower voltage and find the lowest it can run on at stock (Boot) you can actually train AMD CPU's to respond to and utilize lower voltage when Overclocking Most say that is a Myth but I have successfully done this with every AMD CPU I have since I read this 2 years ago Maybe its and I am just lucky but 6 AMD CPU"s later I really believe that its achievable from my results and what I have experienced at least.