I have the retail copy of snow leopard and wanted to know if I should be able to run the hard ware test on a Mac Pro 1,1. I have tried but nothing, it just goes to the apple and boots up. Yes I am holding 'D' down at boot, with a wired keyboard. If i can not run the diagnostic from the SL disc how then? I dont have access to the original discs this machine was shipped with. thank you. PS I also have the Tiger retail CD's. Would they work?