Your chip may or may not reach the same overclock that some other people reach.
Set it to the speed that you think will work, run prime95 for a couple of hours, monitor the CPU temperatures while running prime95. If everything is good so far then you can say it is good. Or if you are more cautious like some people you can let it run prime95 overnight.
You can check the latest Toms system builder marathon $2000 build and see what they used to overclock their 2600k. (Or the $1000 build to see what they got with their 2500k).
You should hit 4.8GHz by setting your voltage to 1.4 and multiplier to 48. You can shoot for 5.0GHz by setting your voltage to 1.485 and multiplier to 50, but wouldn't recommend the 5GHz mark. Check out this video...
@cia24 You really should not try to bypass the normal trial and error booting to discover what multiplier runs at what voltage as has already been stated each CPU is different, each hardware combination is different and yields different results.
You don't want to run any higher voltage than absolutely necessary to run any multiplier level, short cutting this is dangerous, it takes time and effort to discover what you're after, a quick fix is not the best alternative.