Ultra ATA UDMA

I took the Ultra ATA cables off my Maxtor IDE hdds
to use them to build a comp for a friend, ever since I have tried to reinstall them on the very computer they came off of they cause the BIOS to not recognize the drives and thus hangup…I have tried everything I can think of from going back to the MS drivers to VIA BusMaster IDE drivers and VIA BusMaster Filter drivers all to only pull my hair out…any help be most appreciated, signed “Goin’ Bald”