Yes, firstly you need to identify if the NIC is onboard or in a card slot.. If onboard then we need to know your PC chipset (can't remember the program (something like everest I think) but I'm sure Zing will be along soon to tell ya
)
If in a card slot then you might have to take it out and give us the main chip number/or model number..
Once we know either way we can point you to the drivers for it
As far as the OS disk is it marked GATEWAY? if so then yes it could have the drivers on it..