Overclocking that cpu is an involved subject, easily fill up a whole page, so that's not an easy answer, I'd suggest you Google it. Repeatedly. Read everything, watch everything that pertains to that cpu, that mobo etc.
Every cpu is different, so will have different limits, it's called the cpu lottery. If cpu cooling isn't a factor, you could hit @5GHz or as little as 4GHz before not being able to get stability in any way. As is, OC limits will be determined by a few different factors. Cpu lottery, cpu cooling, ambient temps, psu, airflow, your knowledge of OC, your motherboard, your ram, just to name the most obvious. So a definitive number is not possible to answer either.