Next, to unlock the voltage control, under the "General" tab you will find a check box for "Unlock Voltage Control." Check it and apply settings. This does not always unlock depending on the current drivers and software version. If this does not unlock, it has no noticeable impact using air-cooling or even water cooling. No one outside of NVIDIA knows how much this slider impacts an overclock. I have reached the same results without it enabled. It might be at the point just a relic from the past when voltage control was an option. The truth is I have not noticed any difference since the Pascal generation with it disabled versus enabled.