CPU Input Voltage (CPU VRIN): This is the voltage that the motherboard provides to the CPU, and the CPU then takes this voltage and produces all the other voltages. The default for this voltage is 1.8v, however, increasing this voltage can help a little bit. I would stay under 2.1 on air cooling, as increasing this voltage will increase the delta between this and the other voltages, which will increase the internal CPU VRM's temperatures.
cpu core 1.4v太高？
This is the main voltage to the CPU Core domain. Default for these CPUs is around 1.00v, I suggest staying under 1.35 to 1.4v on air/water, as cooling anything above 1.35v seemed to be impossible with 100% load. These CPUs do throttle between 80C and 90C.
Read more at http://www.tweaktown.com/guides/6755/intel-core-i7-5960x-extreme-edition-s-spec-qfra-cpu-overclocking-guide/index3.html