That depends on a number of things, names the "silicon lottery" (if your CPU can actually go that high), your motherboard, and, also, if you have a decent PSU. Also, what aftermarket cooling solution do you have...?
As kind of a crude comparison, though, the former, the TDP of the FX-6300 is 95w. The FX-6350 (a factory-overclocked FX-6300 with a speed of 3.9ghz) has a TDP of 125, which is the same as a stock FX-4170. So getting to 5 ghz is going to take a lot of oomph.