Hope this help because I oced my 7600k to 5ghz too with 1.275v: the voltage that the mobo supplies to the CPU is not always stable, it can be by the powerline or by the motherboard itself, but is not stable always, so, if the voltage goes down more than the CPU needs, it can cause problems, so, to avoid that, the mobo supplies the processor with more voltage than needed, to avoid damage, and also because that's the way it works, if you specify a determinated voltage, the mobo will automatically rise it up a little bit when it's under load and it will go down to the volts you specified (sometimes a little bit more, as I said, to avoid damage) when it's in idle, do you understand it now? I didn't understood it too the first days as 1st time builder, but later I realized it and now I'm here to help