I've installed Arch 2017.07.01 on a micro SD card in my Dell Chromebook 13 using this guide, and I'm using John Lewis' SeaBios to dual boot. I can successfully get into the boot menuand select the micro sd to boot from, but I then get a Welcome to GRUB! message, and, instead of a GRUB console, i get a few lines of white distortion on top of my screen, with the boot menu still frozen in the background. I believe the distortion is the console outputting incorrectly as typing seems to change it, and it disappears after a while, reappearing when i move the mouse or type, like the screen falling asleep and waking up.
I've already tried doing a full reinstall of arch, commenting out GRUB_HIDDEN_TIMEOUT and GRUB_HIDDEN_TIMEOUT_QUIET, and changing GRUB_GFXMODE to 640x480, but nothing had worked.
Any ideas?