Those boards are notorious for not overclocking well. However, if you can increase your FSB, that will give you some boost, but I don't know what you are trying to achieve. If it's to play more modern games, then you really need to bite the bullet and just upgrade your motherboard, CPU, GPU and memory.
For example, if you're trying to run GTA IV, forget it. No amount of overclocking with your current setup will help without a complete overhaul. And I only say that because it seems just about everyone who wants to get GTA IV running asks about overclocking their system. I'm surprised noone has asked how to overclock a 486-DX/2 to run GTA IV yet!