I have a 1.25ghz eMac that was JUST running Leopard. It was running it over 5 years no problem. I had to reformat it though so I put the Leopard disc in. It automatically ejects it because it cannot read DVD RW. So I got an external USB 2.0 DVD RW drive and I saw the disc on the desktop. I restart and hold C... Computer boots normally. I restart and old option for startup manager. Disc does not show up. So I reformat with the Panther disc. No problem. Now the DVD is not even recognized on the desktop. Try the other 2 options, same problem. So why can I not install Leopard yet I had it on here less than 25 minutes ago. I tried the Apple Superdrive and that only works with the new iMac's or Macbook Air. Fail on Apple.