You will have to look for info. specific to that family of CPUs. They do power and multiplier differently than other generations. Turbo Power Limit (TPL) adjust Watts, not Voltage.
And you need to raise the Turbo limit which may not be called multiplier but but Turbo Speed, or Turbo Ratio Limit. The CPU will limit itself based on temperarure and power draw. The Hyper 212 is a good entry level OC Cooler but with an OC 6 core CPU you may find yourself wanting more later on.
If you have the X58 chipset here is a forum on this. there are some limits to respect with this CPU, and the memory controller is on the CPU so don't ignore that aspect of it. But with the unlocked CPU you might not have to deal with that very much...