There are a few overclocking programs that i heard of.... u have to pay for most of em. i use turbo tray 498(498 mhz) on my 300 mhz basic axim, it runs very smoothly and best of all its FREE! now the negatives about it is...... my 300mhz locks up 30 % of the time when i try and change speeds, and it drains more power, other than that this program is very usefull. i did some bench mark tests on 300 mhz, 400 mhz, and 498 mhz. as expected 300mhz is slowest and 498 mhz is the fastests. i didnt see a big difference when i was playing my movie, but game loading times lowered, and best of all emulators like pocketnester and pocketsnes ran much faster, im playing street fighter 2 tubro right now :D
here is the links to tubro tray
http://elevatedstudios.com/pocket/
HAVE FUN!