Thread:Talk:BeagleBone Black Extracting eMMC contents/BeagleBoneGreen/reply

The .dtb files should differ as the Green does not have HDMI. am335x-bonegreen.dtb should exist on newer images. It seems your problem could be related to the version of u-boot not aligning with the contents of the microSD card. Did you try holding the BOOT button when applying power to make sure the microSD card version of u-boot ran?