I got a computer from work with a ton of software, but it is running 10.4.11. I want to get it up to 10.5. I have a Leopard install disc that worked perfectly on a G4, and will also work on an Intel macbook, so I know the disc is ok. When I put it into the G5, the computer spits it out. It will take any other disc, like a movie or software. It specifically hates this disc. So, I made a bootable USB from the disc image, which also works on the macbook and G4. When I restart the G5 with the usb plugged in and hit the option key, it doesn't see the USB. The USB shows up on the desktop, I'll start the installer and hit restart in it, and then it just restarts the computer and does nothing else. Then I tried plugging in an external disc drive. Same deal with the usb, it just restarts, doesn't launch the installer. Doesn't show up when I start with the option key. Then I tried hooking up via firewire the G4 and G5, starting the G4 with the t key. The G5 only sees the G4s HD, not the USB or DVD in it. I haven't tried the firewire deal with the Intel, but I will momentarily. I am not very hopeful. Ugh ugh ugh!!! Any thoughts? I'm wondering if perhaps there could be some sort of setting, since I haven't erased this computer because I want to keep the software.