has anyone encountered this problem?

my yamaha 6416s scsi cdrw is not detected by the bios. i used to before i tried to install linux. i have reinstalled the drivers for the cd and scsi adapter and still nothing. i have tried to update the firmware on the cdrw to 1.0d and still nothing. i went back to 1.0c and still nothing..it used to work prior to the install. i have tried using another scsi card (adaptec 2940au) and still the same thing. is it the drive itself?
i tried burning something..it can using the xp built in burning capability and it can burn using nero. however, it just doesnt read the cd afterwards or any other burnt cds..it just says that the media is corrupt.
i noticed that its filesystem is RAW where its supposed to be CDFS. i tried reading an original cd..not a burnt one and it reads it fine. im thinking this is because the cdrw is not being detected properly in the bios...
anyone else have any ideas??? i have searched all over and have seen posting of people having the same problem..but no one has been able to resolve it...doesnt anyone have any input in this. any help is much appreciated. thanks.