As I see the spec for you board:
http://www.epox.nl/products/view.php?product_id=364 , it sais it has a NForce 2 chipset.
If you have settings in the bios to up the FSB, up/down the
CPU multiplier, and up/down the voltages you can overclock it without a problem..Can't say how much, 'cause overclocking really depends also on the quality of the components. You can also try with a tool like Clockgen (
http://www.cpuid.com/clockgen.php) and try to up the fsb a little, and with
Cpu-Z you can see some caracteristics of you
Cpu and mem.
Don't play too much with the voltages because you can burn that
cpu/board.
Good luck!