Maybe this is INT15 or/and INT13 problem coreboot or SeaBIOS?

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boot OK - image pxe gpxe: http://www.youtube.com/watch?v=bugMlEQwC70

boot fail - floppy fdd: http://www.youtube.com/watch?v=b9aP2srjqXs

boot fail - image grub4dos usb: http://www.youtube.com/watch?v=428Sh441z1Q