i was trying to help someone else out with this similar issue recently but, on your specific motherboard, it lacks several CPU voltage settings including the VCCSA (System Agent or CPU's integrated memory controller) voltage, Load-line calibration settings and offset voltage (this one can be extremely handy when using overclocks above 4.5GHz+. it'll properly downclock the CPU when idling, which in return would further help preserve the life span of the CPU as well as keep maximum temperatures lower as opposed to using fixed voltage).
you can try using OC Genie and then customizing the few options you have from there. besides that, there's not much left you can do. if you wanna upgrade to a newer motherboard, id recommend a Z77X-UD3H for the price, it's absolutely rock solid and handles overclocking/extreme overclocking very well.