Digitest does not work above 7 cards.. I don't know, it has always given me problems.. maybe it was not written for more than 7 cards. I checked the cards in pairs (a Core and another card) and I ran the Digitest on all the cards individually to make sure they worked (several were discarded, they gave errors). I mounted everything, opened ProTools and loaded 24 tracks occupying almost all the slots of the DSP with TDM.. I ran the song, no blocks.. in fact, on the display of the system used, the PCI bus sector never went beyond 50-60%.. maybe if there were more PCI slots, you could think about 15-16 cards before sending the bus into crash.. put two Magmas in series?? It would be a nice experiment.. The chassis is the classic 13-slot Digidesign.. the cable, many years have passed, I could not teach it.. I'm sorry.