network cards

I have a Packard bell imedia 6350 with a 1G AMD-K7-2 chip running WinME. The motherboard is a Halley (MS-6340). I am trying to set up a broadband connection via a cable modem. The installers have tried to fit 2 network cards – Netgear FA311/312 and a 10/100 Lan card (EP-320X-S1). Both fail to install – the system does not recognise the card when restarted. Can anyone help or point me in the right direction?