LAN problems

[tw]

Originally Posted by busterb

The spec. for my LAN. NVIDIA nForce®4 SLI™ MCP built-in Gigabit MAC with external Attansic PHY
Support TCP/IP Acceleration.

This is useful information. Now look on that motherboard. Find the Nvidia chip. Look for its part number such as Mxxxx where xxxx are four digits. Then look here for furthermore information:
http://www.nvidia.com/page/uli_drivers.html
http://www.nvidia.com/page/pg_20030918437537.html
http://www.nvidia.com/page/search.html?keywords=gigabit

Upon quick glance, I don't see any diagnostics from this manufacturer. Asus (and I don't remember) may offer diagnostics but charge for them. Above might provide the latest drivers.

Well appreciate why an industry that no longer understands basic diagnostic procedures also no longer provides hardware diagnostics. A shame because you are now a victim. We cannot even tell is the MCP chip is defective.

That Nvidia communication chip actually uses something called Hypertransport bus but appears to Windows as if on PCI bus (just like that external card). If the hardware was problematic, then other functions such as USB port may also not operate. These many functions are in the same hardware. Yes, some failures could make only the gigabit port not work - again why we really need diagnostics - why we are still speculating rather than solving.

Well, maybe look at some of the latest drivers direct from Nvidia to see if your driver version numbers are same.