I have a rev A iMac g5, with 10.3.9 running smoothly. I need to upgrade to 10.4 for protools, and I have the disc. When i put the disc in the superdrive, it shows up as a tiger disc, and I run the installer which asks me to restart the computer for the install to take effect. restarting the computer results in me ending up at my desktop again, like nothing had happened. When I try booting from the cd drive, or making it my default drive, it takes a little longer for the computer to boot; it shows a mac with a question mark on it for about 2 seconds, than procedes to boot as normal. Any suggestions?