windows XP installation

I cannot install Windows XP on an ASUS P5A motherboard. The installation program repports the message: “There is a conflict with your motherboard and your graphics-card”. My graphics-card is a ASUS riva tnt2 ultra (AGP).
I have updated to the latest ASUS P5A bios and the latest ASUS riva tnt drivers, but still the same message.
What can I do to remove this conflict ??