I recently acquired a G4 (M8493) at auction that did not have a screen. So, until I buy a screen, I have been wondering which processor, optical drive, and second drive the unit has. I took off the heat sink to inspect the processor but no numbers or letters were present. I cannot see anything that will clue me in as to which drives are in both bays. I am a total newbie to the Apple world and am anxious to learn about these wonderful machines. Please advise...