Question Is flash section of BIOS isolated from remainder of BIOS info ?

[wpshooter]

Let's take most more recent/modern Dell desktop and laptop computers. They have an option on the initial bootup menu which allows the reflashing of the BIOS via using a bootable USB stick with a copy of various BIOS versions files which can be downloaded and are applicable to that device.

My question is if the original BIOS on the MB has been come corrupted, is the BIOS bootup function which allows for the re-flash of the BIOS "isolated" from the remainder of the BIOS settings to make sure that even if the remainder of the BIOS settings, etc. become corrupted that the flash function is still intact to get the BIOS reflashed via USB device ?

Thanks.

 

[VirtualLarry]

My question is if the original BIOS on the MB has been come corrupted, is the BIOS bootup function which allows for the re-flash of the BIOS "isolated" from the remainder of the BIOS settings to make sure that even if the remainder of the BIOS settings, etc. become corrupted that the flash function is still intact to get the BIOS reflashed via USB device ?

Kind of. There's generally the Main BIOS, that handles settings, menus, booting, etc, and Bootblock, which handles low-level initial hardware initialization (think, CPU, cache, and RAM). It also can checksum the whole BIOS or Main BIOS area, and if it doesn't match, it initiates a BIOS recovery, the details of which are often mfg-specific.

 

[wpshooter]

So, if you do the flash from a bootable USB drive and it runs successfully thru the process, you can be fairly confident that you have a viable BIOS ?

Thanks.

 

[VirtualLarry]

So, if you do the flash from a bootable USB drive and it runs successfully thru the process, you can be fairly confident that you have a viable BIOS ?

Thanks.

Probably? But there are reserved areas that have to be flashed separately, like the Intel IME stuff, and AMD's Zen PSP.

If you're trying to get rid of a virus, well, not gauranteed to overwrite the reserved and "protected" areas.