PT 6.4, OS 10.3.9, G4 733 1.125 GB RAM. Single HD Card. 96 I/O interface (non digital) Never had a problem since I made the purchase last year. Upon loading PT, it launches all of the plugins, etc, then I get the infamous 6004 error. Digitest says the card is fine. Reseated the flex cable, no change. I don't know if the green light around the power button changes with errors like the Avid Adrenaline hardware....for the record, it's green. What else could I try? Thanks all!