Posted October 01, 2015
timppu: How it works is that the BIOS has two banks, active and backup. As the name suggests, the active bank is the one running. When you perform the BIOS update, it is actually the inactive backup bank that is being updated. Only if that backup bank update was successful and the checksum matches, that bank is made active (and the bank which was earlier active becomes the backup bank).
I don't think it goes that way. The active BIOS bank is the one which is programmable be a user and needs power to maintain data within. If you flash bios - you programm this user-updatable bank. If you misflash it - you have to take out battery (and/or dabble with jumpers) and after restart bios from backup non-programmable bank is written to a user-programmable bank. Back in the days you COULD brick your PC with misflashing bios (my friend did so by trying to have custom logo which appeared to be to big and overwrote bios data :-). But starting from at least 2000 - motherboards usually are equipped with backup banks and I don't think you can easily brick a PC during update process...
Post edited October 01, 2015 by tburger