Canonical no longer releases Ubuntu for 32bit PPC processors
Canonical is dropping support for 32bit PPC processors with version 17.04. The organization has announced this. According to Canonical, there has been little interest lately and that was reflected in the number of downloads of the image.
In addition, there will no longer be support for the processor architecture in Debian in the future, so a community of volunteers should continue to provide support, Canonical writes. The last version with support remains 16.10. Those who want support for longer can continue to use 16.04 LTS. That version will be supported until 2021.
Support for the outdated processor architecture disappeared from more and more operating systems in recent years and Ubuntu was the best-known Linux distro that still had variants for the architecture.