I thought the LAN (ethernet connection) was a port on the I/O board that also has the JVS connection. Also, the Yellow Lindberghs I've seen all used a separate sound card for audio, never the built-in connectors were used.
A complete yellow Lindbergh has 3 slotted cards:
- AGP Graphic card
- PCI Sound card (with 2 CINCH ports)
- I/O card (with JVS USB port and LAN port, however this LAN port is not used to link multiple games, that is done using the motherboard built-in LAN port).