Is this cooler good for overclocking the i7 6700k?

[Silent Shot]

Is the Cooler Master Hyper 212X gonna keep my core i7 6700k cool when I overclock it to the maximum without messing with voltages?

[WoodenMarker]

The default setting for voltage is auto and isn't recommended for use with oc'ing. It's usually more than necessary.

The 212 Evo is enough for pushing ~1.2-1.3v depending on the scenario. 

[ThomasD]

Power formula tells us (roughly) that heat output rises linearly with frequency, but geometrically with voltage.  Practically speaking this means increasing clock speed has minimal effects and most of the increased heat generation of overclocking is due to the added voltages.

 

As Wooden Marker notes, if you increase the clock speed without changing from auto setting your voltages will automatically rise as the chip tries to maintain stability at the higher speeds.  So when you OC make sure to limit actual voltages to normal ranges.

 

If you do that then your cooler should be more than sufficient at whatever clock speed you can get stable.