GeoDsp: Images to display the geometry as the BIOS has choosen to interpret it. Both images are intended to be written to the first ~8MiB of a raw device (ie /dev/hda, /dev/sda) and be over one large cylinder of 255*63 512-byte sectors in size. To save the existing data for restore later: dd bs=1M iflag=fullblock count=8 if=/dev/sda of=sda.img GeoDsp1S is a one-sector variant containing all code in one sector that is intended to test behavior with a typical MBR/partition table layout. A partition table should be written after writting an image. GeoDspMS is a multi sector variant intended to look like Syslinux installed on a file system on the raw device (as opposed to a file system within a partition). GeoDspMS can also be used to attempt to make the boot sector look like a normal file system's boot sector (ie FAT12/FAT16/FAT32). In order to do this, you must first save a portion the existing boot sector (the majority of the BIOS parameter block). dd bs=1 skip=3 count=87 if=/dev/sda1 of=sda1.bpb dd conv=notrunc if=geodspms.img of=/dev/sda1 dd conv=notrunc bs=1 seek=3 count=87 if=sda1.bpb of=/dev/sda1 dd bs=1 skip=3 count=87 if=/dev/fd0 of=fd0.bpb dd conv=notrunc if=geodspms.img of=/dev/fd0 dd conv=notrunc bs=1 seek=3 count=87 if=fd0.bpb of=/dev/fd0