Yes, you can get 4.4GHz on a 8120 on air. The temps will be even better with the Kuhler. I have a Kuhler 620 and I have had high end $75+ air coolers. The Antec is better by a degree or two, not huge but it's still a nice cooler. Run a push/pull configuration with the fans and get a better thermal paste like Antec Formula 7 and you might even hit 5.0GHz at a safe temp. That's a big MIGHT though.
No one in this thread has said they have the same CPU...I have an Intel i7 2600. stickg1 has an Intel i5 2500k.
If you truly want to learn how to overclock you will need to learn how to do it...not just have someone give you the answers. If something does not work, how would you fix it? Ask someone to then fix it?
Yes, I have an i5-2500K and it is nothing like having a FX-8120. In fact my max temp at 4.5GHz is 60C, which is good for i5 sandys, but really high for your FX-8120. So there is no comparison there. You're just going to want to adjust the multiplier and leave it on auto voltage until you reach instability. From there you will need to monitor voltages and adjust them accordingly while also minding the temperature and making sure it is safe.