Hi Tom, We would need a bit more details about your patch before we can apply it. 1* What is the register that cause the problems? How did you come to it, starting from the problem you encountered on that motherboard? 2* What are these values 0x02 and 0xFD you are using? Why do you say that having 0x02 in that register is an "unknown" state? 3* How well-tested is your patch? Did you test it on a "standard" piix4 chipset? Thanks. -- Jean Delvare http://www.ensicaen.ismra.fr/~delvare/