tryf :
So u think that changing the fan wont change anything?
Well your 8300 is OC'd really high so it could just be it's going to be hot no matter what and the hyper 212x won't be able to support that especially if your mobo or your case isn't properly set up to allow good air flow. Like if it's in taking hot air and exhausting it through the back then there's no cool air to properly cool the chip.
I just recommended a liquid cooler because with OC's that high you'll get better cooling results in general.
You said you had it at 4.4ghz right? I'm not sure why you have it OC'd so high to be honest, it seems unnecessary. That is, I don't know which 8300 you have (8320? 8350?) so I could be off base here.
The fan could be the issue as the ones that came with the cooler are specifically designed for it, and with no air coming out the back fins (I'm assuming you mean the back of the cooler towards the exhaust fan on the upper back of your case) it's not really pulling out any heat from your CPU. So heats just trapped there.