Ever since I got my computer with Win 7 Pro in Dec 09, I’ve been faithfully
backing up and making system images with the built-in Backup and Restore
feature. When I got my laptop it had BIOS version A04 installed by the factory.
I’ve since upgraded to version A08 based on a recommendation by the built-in
Dell diagnostics utility. On the Dell support website (drivers and downloads)
version A08 is the only listed BIOS for the Vostro 1520.
If I understand things correctly (not always the case!) the BIOS resides as
flash software within the CPU which is on the motherboard. It’s the BIOS that
kick-starts the operating system. If the BIOS becomes corrupted or fails, your
computer becomes a paperweight. During a backup, system image, or creating a
restore point, only the hard drive is copied. The BIOS is NOT included. I can
verify this if I use the Dell Recovery Manager and return my computer to
factory settings or use one of my earlier system images. All of the junkware
returns, but the BIOS still shows as A08 at startup.
When a person updates his/her BIOS, will it be backwards compatible? In
other words, if a computer experiences issues and the BIOS is updated as part
of the corrective action, and then the computer has to be returned to it’s
original factory state, or to an earlier system image, will the newest BIOS
always be compatible? If there’s a chance the BIOS will not be compatible how
does one make a backup of the earlier BIOS(es) if they’re no longer supported
or available at the Dell website?
You have a very good understanding of what a BIOS is, where it lives and how
it’s not backed up. In fact, I feel like you’ve written half my article for me.
But you also raise a very important question about backwards compatibility.
I’ll address that, and clarify a couple of the items you mention.
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The BIOS doesn’t really reside “within” the CPU, rather it’s typically a
separate chip on the motherboard. The difference is perhaps a technical one,
but what’s important is that the BIOS is not stored on your hard disk or, for
that matter, related to your operating system in any practical way.
The most important point is that the BIOS is not backed up by backup
There are many reasons for this, perhaps the most common is the practicality
of a backup program restoring it. While there’s certainly a standard – perhaps
one of the oldest PC standards – about reading the BIOS there’s no standard way
to write to it. Backup programs might be able to save a copy of the BIOS, but
if you ever needed that copy they wouldn’t really know what to do with it.
Add to that the fact that the BIOS is typically somewhat complex to write
to, and the result is that it rarely needs to be “recovered” in the same sense
that data on your hard drive might need to be.
Bottom line: backing up a BIOS isn’t really all that necessary or
The only way I really know to backup BIOS would be to download the BIOS
update utility from your computer manufacturer that corresponds to the version
of the BIOS you have in your machine. If you ever need to re-flash it, you’d
have that utility to do so.
The days of a corrupt or failed BIOS turning a computer into a paperweight
are, fortunately, pretty much behind us. Most motherboards have some way to
reset the BIOS to some initial state or version – often with a jumper or
connector you physically move on the board. Once the original factory-default
BIOS has been put into place, you can then typically use the downloaded update
utility to then take it to a more current version.
Almost by definition BIOS updates, when installed on the motherboards that
they are intended to support, must always be backwards
compatible. I’ve not heard of a case where they’re not.
There is a theoretical problem if some random software relies on a bug in
the BIOS that is subsequently corrected, but that’s extremely rare, and in most
cases fixing the BIOS issue are more important than a badly behaved
In general, however, you should feel safe updating a BIOS, as long as you’re
doing so with the correct version for your specific motherboard.