If nothing in this document proved helpful, or at least not helpful enough to get your machine working, your best bet is to write up a message that fully describes your difficulty, what type of UDMA controller you have, whether it's onboard or on a card, if your drive is actually UDMA or plain EIDE, exactly what configuration of drives you have, what version (distribution & kernel versions if possible) of Linux you're using, and anything else that sounds useful, and post it to the newsgroup comp.os.linux.hardware. You'll probably get some helpful suggestions soon.