You can change the resolution via SSH using the following commands (login as 'chip' user, not as 'root'):
chip@chip:~$ export DISPLAY=:0
chip@chip:~$ xrandr --output HDMI-1 --mode 1280x720 --rate 60.00
You can see more of my observations here: https://bbs.nextthing.co/t/just-got-c-h-i-p-and-the-screen-keeps-going-black-on-and-off/11595/3?u=mikakoskiola