Can I overclock an Intel Core processor not in the K series?

I'm looking at an 3rd Generation Intel Core i5-3570 to run on an ASUS P8H77-V motherboard. I've heard that the K series on Intel Processors are highly overclockable but does this mean a non-K series is less overclockable or not at all? Suggestions on motherboards and all else is well appreciated.

What is a VPN?

VPN is (Virtual Private Network) were first used by companies to enable their employees to securely access internal systems such as email remotely (e.g. from home or while on business trips). Today they are increasingly being used for personal use by individuals to protect their privacy while online in public places (e.g. when using the wi-fi connection in a cafe) or in a country where the internet is censored / blocked (e.g. China, Saudi Arabia…).