My Power Macintosh 7500/100 won't read CDs, it can read them, the drive sounds like its working then it stops but no CD icon on the desktop. The Mac is running Mac OS System 9 I don't know why it stoped, and can anyone tell me what is the name of the CD drive for the 7500/100 is it the Apple i600? I have 3 mac CD drives, I want to know which one is the right one!