Static IPs won't help. If you can't get an IP via APIPA, that means you don't have physical connection to the router even though the TCPIP stack is working properly.

Did you install the Nvidia firewall? if so, remove it. I've seen that cause problems.

If there was a storm, it's possible that the NICs got damaged. Electricity is a crazy thing.

By network bandwidth, i'm guessing you mean Internet. Most ISP don't come anywhere near 10Mbps, much less 100.