Probably not in the usual way. You will probably get a message that you can’t use those disks to install on an unsupported machine. You could try and port it across by making the TiBook a Firewire Target disk and using a backup utility like SuperDuper to write the new system. The nice thing about SuperDuper is that it will replace only those files on the TiBook that are updated on the iBook (like Tiger) and make a bootable Tiger Volume. The only problem might be that there a few system files absent in the Tiger install on your iBook that are needed to make the TiBook bootable, so be careful! The worst that can happen is that you will have to go out and buy a master set of Tiger install disks (but we all want to support Apple, right?) But by the same token, if you make the a Target Disk of the iBook, you could attempt to start up the TiBook with the internal drive of the iBook and see what happens. If you can do so successfully, you can probably just copy the system across using your backup utility. jg On 24-Jul-05, at 10:57 AM, Jeffrey Gonzales wrote: > I have an old TiBook 550 running on Jaguar. Recently i bought an ibook > with Tiger already pre-installed. > Can I use the Ibook Tiger install disks to upgrade my TiBook?