Appendix D: Dual Boot Block
D-1
Appendix D
Dual Boot Block
D-1 Introduction
This motherboard supports the Dual Boot Block feature, which is the last-ditch
mechanism to recover the BIOS boot block. This section provides an introduction
to the feature.
BIOS Boot Block
A BIOS boot block is the minimum BIOS loader required to enable necessary
hardware components for the BIOS crisis recovery flash that will update the main
BIOS block. An on-call BIOS boot-block corruption may occur due to a software
tool issue (see image below) or an unexpected power outage during BIOS updates.
BIOS Boot Block Corruption Occurrence
When a BIOS boot block is corrupted due to an unexpected power outage or a
software tool malfunctioning during BIOS updates, you can still reboot the system
by closing pins 2 and 3 using a cap on Jumper JBR1. When JBR1 is set to pins
2 and 3, the system will boot from a backup boot block pre-loaded in the BIOS by
the manufacturer.
