disk enumeration - The PC Guide Discussion Forums
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Also note that pre-Vista uses boot.ini, which must a) reside on the = initial BIOS's boot disk b) the boot.ini entry uses the BIOS (int 13h) = disk number. The OP must ensure that this number is correct. Vista+ use BCD database, which keeps the mountdev IDs of the disk = volumes instead (for non-Dynamic disk volume, mountdev ID is 4byte MBR = signature + 8 byte StartingOffset of the partition). kept in \boot\bcd as mountdev IDs. In this latter case, the BIOS disk numbering is not important. What is = important is that a) the correct boot disk is known to BIOS, probably to = the extension BIOS on the controller itself b) the driver for its = controller is installed to Windows OS which will be booted. That's all = for Vista+.and best of luck.