I already have a similar question on Ask Ubuntu for installing Ubuntu on a mac, but I want to post a question here. Is that okay?
Questions about installing any operating system on Mac hardware is on-topic here, so feel free to ask related questions here. For a full list of topics that you can ask questions about here, see:
However, keep in mind that cross-posting is prohibited and that you shouldn't re-ask your question from Ask Ubuntu here. If you feel that your question would be better suited here, flag for moderator attention on that question and ask that a moderator migrate it.
With regard to that specific question, whilst it's on topic here, I doubt you'll get any better attention here as IMO it's more to do with Ubuntu than the Mac hardware?