Le 06/08/2016 à 16:18, Felix Miata a écrit :
Pascal Hambourg composed on 2016-08-06 12:01 (UTC+0200): ...If the boot image is in a PBR, the BIOS won't load it directlyIt will if the PBR is on a primary partition on the same disk.
On the same disk as what ?Do you mean that the BIOS can load directly the boot sector of a primary partition instead of the MBR ?
It's how all my systems boot if I'm not using IBM Boot Manager as the primary bootloader.
What do you call "IBM Boot Manager" ? Is it the boot manager used by OS/2, or the generic/legacy boot code in the MBR used by MSDOS and Windows, which loads the PBR of the primary partition with the boot flag ?
Also, what does your MBR contains ? Only the partition table, no boot code at all ?
After reading your reply I made a quick test on three different PCs.I installed a generic MBR boot code on a USB stick and checked that it could boot on each PC and load the PBR of the primary partition with the boot flag. Then I erased the boot code (first 440 bytes in the MBR) with zeroes and observed that the boot hanged on all my test PCs, so I concluded that the BIOS still tried to load and execute the MBR because of the boot signature at the end of the MBR. Then I also removed the boot signature in the MBR and observed that the BIOS said the device was not bootable, as expected.