Currently Being ModeratedMar 17, 2013 1:15 AM (in response to kunam86noumea)
Welcome to the Apple Support Communities
The most recent OS X version that a PowerPC-based Mac can run is Mac OS X 10.5.8, so you can't use OS X Mountain Lion. You need a new Mac if you want to use Mountain Lion
Currently Being ModeratedMar 17, 2013 8:12 AM (in response to mende1)
Sorry, you need a newer Intel Mac to run OS X 10.6-OS X 10.8 (Mountain Lion).