Problems accessing the Internet

I have OptiPlex GX280 and I recently reinstalled Windows XP with service pack 2. When everything had finished loading after the installation, I was unable to access the Internet nor was I able to reconnect to the home network through a D-Link DI-604 Router. I looked at the I went to device management and found that I had no drivers for an Ethernet Controller and some other audio, video controllers. I found out what device I have for the first(BCM5750A1 NexXtreme Gigabit Ethernet PCIe) figuring if I have internet access I can manage the rest. I went to dell's support page and downloaded what I thought was the correct driver. I installed it, rebooted, and I still have no access. Can anyone help?