Well personally I would not clock my system, I honestly fail to see any need, and its not like I even have the fastest most extreme model of CPU out there, I have the a 3rd gen i5-3570K, not the fastest but seemed like the best value CPU on the market at the time, and is a clockable CPU, its even on a Z77 chipset board, inside CoolerMaster COSMOS S case kitted out fully with all Noctua fans, one of the older models of Thermalright heat sink units, heat sink was considered one of the best at the time and sold without a fan and advertised as been able to handle perfectly well without one, but still I put a optional 140mm Noctua on it. I have never seen a single core on that CPU reach over 50c, around 20 to 30c, every seen it as low as 12c on occasions, to see my CPU running at around 22 to 28c is not an uncommon site.
So basically this set up would be ideal for clocking but, still not going to do it because there is no need, but having everything there in a position so its cruising at standard speeds with such ease, everything I run on here is smooth, does never locks up never crashes anything, am yet to see it struggle to run anything, and I have run over 2,000 hours of a modded up version of Skyrim on this PC before, so my set up is living proof imo that running standard speeds in conditions that clockers could use easily, gives you a much healthier more stable system, which suits be better than any pointless extra speed I would get from clocking.
Standard the CPU does its own boost thing up to 3.8 per core anyway from 3.4. but I would think since that heat sink posted is the modern day version of what I have so its going to be better even if only slightly, and if I can run an average temp of 22 - 28c on this set up, well you tell me what you think someone serious about clocking there system could creep there system up to who is starting out with a more modern latest gen i5 or 7, I don't think I would struggle to take my speeds up to 4.8 right here and now if I wanted, so I'm would guess that is a capable sink if you wanted to go to extreme.