I've tried several different Linux Live OSes, including the Knoppix 5.0 DVD.
Knoppix says it recognizes my ethernet card, which is a built in NForce as part of this motherboard:
http://www.msi.com.tw/program/suppor...UID=702&kind=1

Knoppix says the device is working correctly, but then when I try a URL, I get "Temporary failure in name resolution".
When I try the DHCP configuration with an IP address, I get: "Network is unreachable"
When I try manually configuring using settings from Windows, I get "No route to host".

Everything works fine with DHCP (or a manual configuration) under Windows XP, so it's not a hardware problem.