GA-73VM-S2 Problems?

I have a computer with a Gigabyte GA-73VM-S2 motherboard, 2gb of G.Skill RAM, and a PCI NIC card. The only problem I'm having is that the NIC just absolutely refuses to work in either PCI slot. In the device manager, the NIC will sometimes show up as "PCI Device", and when I try to update the driver with the correct INF file, it says that it is an incorrect INF file. And now whenever I plug in an ethernet cord into the onboard LAN port, it still says that it's disconnected. Something is up. I think that the motherboard may be defective... I am running Windows Server 2003.

Also, this has been happening at random times.

Edit: I am trying to reinstall the chipset drivers; they are a real pain to install. This may do the trick, as the previous installations were somewhat buggy. We'll see.

Edit 2: Just installed the chipset drivers, yet no avail. I've also noticed that it takes a considerable amount of time to open the Network Connections window. And now the onboard LAN will not work at all. I'm coming really close to an RMA.

Any suggestions?