It depends on your computer. My G5 Dual 2.0 running OS 10.4.x uses the Digidesign SCSI 128 Kit--search for info, and you'll find out which ATTO card it uses. (I don't recall.) The G4 that preceded the G5 used a SCSI 64 Kit, which I think included the express pci dc card.
I'd be surprised if Digidesign's compato docs do not include the answer in the legacy products section.