How to boot from SD Card

Hi, So I have download Ubuntu and burn it to a SD Card, and I have placed into my VIM1. I have tried a few things, I have placed it in there and power now. Nothing, and I have press the space key it hopes it will boot from the SD and nothing. Boots into the Android that is pre-installed.

What am I doing wrong?

Hello @terrorpup,

Check the documentation for entering upgrade mode to boot from external image media.