Since this keeps getting upvoted and downvoted in waves and is thus obviously garnering some attention, allow me to point out that the Khadas Edge 2 is a pretty amazing ARM SBC that runs Ubuntu just fine, and would most certainly have been a much better experience for the OP.

It's on my list of prospective Xmas "self-presents", although I would still need to spend a little more to match the devkit specs (although it is available in a "pro" config that is closer).