Given the fact that motherboard only has a 4 phase power regulation system I would not try and overclock an i5 on it. The highest you're going to get is maybe 4GHz, and I doubt that would be stable. These boards are business boards, not designed for overclocking anything except perhaps things like the new Pentium.
Trying to push the voltage required to successfully and stably overclock an i5 would require enough voltage to severely degrade the performance and lifespan of that motherboard. If you haven't bought it already, don't be a cheap ass and get a proper overclocking motherboard, or don't bother getting a K series chip because either way you are wasting your money.