Radeontool is currently not keyworded ~ppc, but it works very well on PPC hosts. It would be very kind of you to keyword it. Reproducible: Always
Created attachment 128746 [details, diff] Patch to apply to the radeontool ebuild
Seems to mostly work, light [on|off] doesn't seem to work here, but otherwise, it's okay. :) Marked ~ppc, thanks for the report.