You need to install the right drivers for your nic-card, for win-xp you can get the drivers and specifications for your system at the HP web site.
I've done some looking around and the Intel 82562GT chip set your notebook has is problematic. Take a look at this posting Here
I did some Googling and haven't seen any real solutions for linux. Maybe someone else on this site will have a better answer for ya. The driver for win-xp should work, but you may want to look into flashing the bios also.