i have a hp pavilion g4-1201tx laptop with win 8 pro 64 bit. and winxp,,,,my ethrnet wlan works fine in win xp but in win 8, t

Seems like a driver issue, there does not look to be a driver from HP for the wired lan card from HP, you may need to contact HP for support if there are issues with it working. You can also try doing a Windows Update to see if there are any newer drivers for the network card.