Panther and Tiger install CDs. They'll load on my iMac but not on the G3. I have an external DVD writer hooked up to the G3 it will list it in System Profiler but I can't access any CD from it, even the 8.6 CD I used to install.

As a side note the drive setup included with 8.6 disk wouldn't format my 40gb IDE drive to HFS+, only HFS Standard.