A friend from work got a G3 from a family member and wants me to update and make it usable. I bought a copy of 10.3 to install on it. The computer refuses to boot to the CD. I've tried every way I can think of. Holding down "C" while booting up, booting up to OS 8.6 (the OS that's installed on there currently) and changing the startup disc to the CD-ROM drive, and opening the CD drive and clicking on "Install Mac OS X." What am I doing wrong? As far as I know, this computer should be compatible. The CD sleeve says system requirements are a G3, G4 or G5 computer.