Samsung Chromebook XE303C12

First generation chromebook from Samsung in 2012.

• Cannot boot from the USB 3.0 port (blue) - USB boot is only available from the 2.0 port.
• Press CTRL + U to boot from USB or CTRL + D to boot from internal disk
• low beep indicates that the machine cannot find a bootable image on the USB drive
• Check that you have run sudo crossystem dev_boot_usb=1 dev_boot_signed_only=0 - the signed image flag is important and making sure it is low (set to 0) is key.

ArchLinux ARM

See Samsung Chromebook 

LinARM Images

see Linarm