x4 860k overclocking

Solution
Depends on your wants and needs. What is this computer used for?

What PSU model and motherboard do you have? What budget do you have for a CPU cooler?

Don't get the 212 evo, look into the cryorig H7


Probably not worth OC'ing at all since Turbo Mode is 4.0 GHz at stock. And you would be turning off TM to do OC'ing.