The main difference besides temps on a CPU cooler is the noise. The stocks one make the CPU work at its rated clocks with no issue, but are not silent. A Cooler Master Hyper 212, is silent, makes your CPU be cool, and is cheaper than the Dark Knight II.
Going just for the stock cooler on a -notgonnaOC- rig won't make any performance difference.
It's not a necessity, stock coolers are perfectly capable of cooling the product they're designed to. Aftermarket cooling is not neccessary if you're not planning to overclock. The two advantages of an aftermarket cooler in your situation would be lower temperatures (which can slightly extend the life of the CPU but unlikely to be noticeable) and less noise.
If you have an overclockable CPU there is really no reason to not overclock. Overclocking these days is so easy and painless... and mild overclocks with a sane voltage have no affects on longevity/degredation.
They're also fast enough to not need overclocking in the first place. The excess heat created could cause an issue if the computer is in a small room or bedroom.
i use the stock FX8350 cooler with turbo core enabled clocks my cpu to 4.2 ghz, i have no troubles wenn extreme heat, only yeah wenn gaming it sounds like a airplane.
yesterday i runed prime95 over an hour, bed room temp arround 23 degrees, and the temps didnt get higher as 45 degrees.
but the noice is horrible.but the cooling performance of those stock coolers are not bad, only not oc on it.
And by the way dont put a FX8350 on a Asrock 970 board cause those power phases 4+1 you will not be able to oc enything, those boards are bad, better take Asus M5A97 evo r2.0 if you can find, or just go on a 990FX chipset board. Asus M5A99FX pro 2.0 Asus sabbertooth asus rog boards, Asrock extreme 9 gigabyte GA-990FXA-ud3.
if you not gonne do any oc then you can put it on a 970 board wo is FX2.0 ready.
I always like to say yes to this. Bigger cooling units = bigger OCing potentials. If you got something like a Phanteks PH-TC14PE, then you could hit 5.0gHz with reasonable temps, but if you got a Hyper 212 Evo, you'll be stuck around 4.2gHz. If you get a phase changer, then you could hit literally any speed that your chip is capable of. A 3930k can hit 5.2gHz, at 100% load, using a phase changer, and still be sub-zero temps. So, more cooling = better.
ofc is a better cooler realy a must have wenn you go into oc, and its also better in everyway. so if you have the money for it, dont schwimp on a cooling, only if you realy on a tiny budget, i should not spend that much in an aftermarket cooling solution in the first place, then i would first spend the money into a better gpu, and next month or so buying a better aftermarket cooling solution.
So, with all that being said, I'm kinda leaning towards overclocking now, but whats a reasonable overclock for gaming thats not overkill? And im switching the motherboard to a Gigabyte GA-990FXA-UD3 and still the AMD FX-8350. Oh and probably keeping that Xigmatek heatsink.