Adaptec 29160N errors

[whizkid at ValueDJ.com]

Hi all,
    I have a AMD ThunderBird 1 gig machine on a Abit KT7A-Raid MB.  When I
install my Adaptec 29160N Ultra 160 scsi card, and try to do any
writing to a DDS2 tape drive, I get a screen full of Ahc0 - Parity
error then I get another error stating that the card is *Reporting*
the errors and not *Generating* the errors, and that parity checking
will be disabled.
    I have tried 2 different cards in 3 PCI slots, and a hand full of
different internal and external SCSI cables and terminators.  The
cards have the latest 3.10.0.0 Bios and the MB also has the latest and
greatest bios. I have also tried a few different scsi backup drives.
    Finally I installed a Adaptec AHA-2940 card, and no errors. I am
currently running freeBSD 5.1-Current.

Thanks for any help you may be able to provide me.