When certain Seagate SCSI hard drives are connected to the LSI 22320 Ultra SCSI Card that shipped as a configure-to-order option in certain PowerPC-based Macintosh computers, the computer will stop responding ("hang") during shutdown or restart.
Apple included LSI 22320 Ultra SCSI cards on some PowerPC-based Macintosh computers as a configure to order option to support the addition of tape drives, but did not ship any SCSI hard drives with the card. If you have added a Seagate hard drive to the card's bus, you should check the Seagate website to see if the drive you have is compatible with the card.
If you determine that a hard drive is incompatible with the card, you should remove the hard drive.
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