How much will I be able to overclock my CPU with this motherboard?

The T4 is not a very good cooler to be overclocking with. It may get to hot to go too high.

Overclocking ability depends on if the CPU is able to or not. Its called the "CPU lottery" where luck comes into play of the ability of the CPU.

I assume around 4 GHZ to 4.5GHZ. Your CPU may get too hot with that cooler.
 


The 212 Evo would be a great choice. Even though they look the same, they preform differently and will give you a better overclock.

All depends if your CPU is stable at a low VCORE.
 


Yeah with air cooling you need a lower vcore to reach 4.5ghz. I was able to reach 4.5ghz on my 4690K with a 1.230v, however my cpu goes up to around 50-60C when running prime95. I have a H100i AIO.

BTW... Prime95 is overkill for system stablization, prime95 is the most demanding piece of software i've ever seen. So if you get high temps with it or after a few hours you get a BSOD, don't worry, you should have a very stable overclock.