I have solved the problem. The Sound Blaster 16 PCI sound card was changed with an ISA (Crystal CS4236) and a Realtek Network card (RTL8139A) in the free PCI port and now i have internet but i still want to make the on-board lan port to work.
The lan port is not a NIC, is an AMD AM2100/AM1500t (I don't know if this is correct, Windows detects it as a AMD lan port and the damn "Everest Ultimate" detect it only when the drivers are instaled)