ASRock P55 Pro - Win XP LAN driver problem

[g4danny]

Hi all, I have a new P55 Pro MB and have a strange problem. After installation of Win XP (SP2) the Realtek LAN controller was not recognized, but this changed by installation of the drivers from the ASRock driver CD. However, the Realtek connection tells me stubbornly that "cable is unplugged", so I cannot use the connection. I know this error message is a nonsense, as I have several times (including now) booted from Kubuntu installations and live CDs, the v9.04 32bit and 10.04 64bit, both of which connect to the internet from the word go. Seamlessly and hassle-free. Does anybody have a similar experience and a solution to the Win XP trouble?
Thanks, everybody!
Daniel