Strange wireless problem

[skippy32]

Hi guys,,
I have just set up an ad hoc wireless network between an XP pc connected via broadband and a toshiba xp laptop using an MSI adapter card. Every 4 to 5 minutes my internet connection from the laptop drops out yet the wireless network is unaltered because I can modify files on the pc using the laptop. I click the sys tray icon for the wireless network and ask windows to repair the connection and it does. The internet then works fine for 5 minutes until I need to do the same thing.
any ideas?

thanks