Check which revision motherboard you have. If you have a revision 2 motherboard you are good to go. If it is revision 1 you will need to install a PCI hard drive controller to avoid data corruption problems. www.xlr8yourmac.com has an article on how to determine which motherboard you have. If you have a SCSI PCI card that shipped with the PowerMac, it will accept most 50 pin SCSI drives. www.xlr8yourmac.com has a drive compatibility database that is pretty thorough.