Raising the Vcore of your CPU usually allows you to overclock it farther, but you need good cooling for the higher voltage. I did some research, and I couldn't find a voltage mod for your mobo, exactly, but there are ones
here, and
here that are for similar boards. One site the author is willing to help you out if it's not listed.
I've never seen a voltage mod for my Shuttle AK31, but it has the same voltage controller as many other popular boards. I just did the same mod, and voila, it works great.
If you decide to go 4 it, forget the soldering. I've found a much better, and safer way to do it with
these. They're little clips made for attaching to the legs of IC chips.
I hope this helps you out,
Doctor