I saw something kinda similar in another thread, it was a bad quartz in the board (there's two, one for the screen, one for firing functions) and maybe both of the quartz in your board are bad? I'm not sure that's it, but it was posted in another geo thread by an eclipse tech:
Originally Posted by 7lash
The problem is with your board, not the firmware: the quartz crystal that provides the timing for non-critical functions such as the game timer, the rof indicator and the backlight has stopped working for some reason.
The board will still do all of the important stuff like shooting (there is another crystal for that) but you should get the board replaced under warranty. You can do this at the 'Cup or before through a Service Centre, the choice is yours. Either way, please make sure that you have registered the Geo for warranty.
Apologies for the inconvenience. It's rare, but these things do happen.