Try starting up with the option key held down. You should be presented with a choice of starting up with either OS. Kathi snip Here's my problem, I was tinkering around with yellow dog 3.1 and installed it on the computer, it went well, and worked. Now I want to install several partitions, one with mac 9.2 and the other for 10.4. I installed my 9.1 cd, and it will not boot from it. I then installed my 10.2 cd and it doesn't see the hard drive. snip