You cannot increase the multiplier (overclock) on a non-k Intel CPU. The 'k' signifies that the multiplier on the CPU is unlocked and can be changed. So, to answer your question, no, the 3570 will not overclock, the 3570k will.
^ so very minimal OC if not K suffix cpu. If you want to OC get the K chips.
There's nothing wrong with overclocking a non-K CPU. Especially with cheap Z75/Z77 boards approaching the price of H77/B75 boards. You get a bit more performance for maybe another $5-10. If you want more, of course you'll have to get the K edition, as well as a better cooler and ideally a better motherboard as well.