Does anyone know if there are any special installation procedures for using PCI Express?

We got 6 new machines this week from Gateway and this is my first look at PCI Express. The machines in question are Gatewways E-4300 (P4, 3.2 Ghz...... dual 150 gig SATA's...SWEET..a waste but sweet).
First, we blow of the Gateway install with our own XP SP2 setups whihc leaves the Chipset, Video, Audio, and NIC drivers to install. No problem, Gateway supplies the disc.
Video and audio install with no hitch and the NIC in question is an onboard Marvel (never heard of them) Modelxxx8050. Also on this disk are the PCI-E install programs so I run both of them with no reported errors.
Device Manager reports no issues after reboot, NIC card receives the proper DHCP addressing and gateway information from the DC but will not connect to the internet.
I know it's something simple so what did I miss?