Для Tumbleweed запустите от имени root:
zypper addrepo https://download.opensuse.org/repositories/home:hibby50/Tumbleweed/home:hibby50.repo
zypper refresh
zypper install intel-undervolt
Для 15.5 запустите от имени root:
zypper addrepo https://download.opensuse.org/repositories/home:hibby50/15.5/home:hibby50.repo
zypper refresh
zypper install intel-undervolt
Для 15.4 запустите от имени root:
zypper addrepo https://download.opensuse.org/repositories/home:hibby50/15.4/home:hibby50.repo
zypper refresh
zypper install intel-undervolt