I should have written, "When I do the BIOS update process, I have the option to also backup the old BIOS before I flash the new one."
I can start the BIOS update procedure and I see that "backup?" option before I proceed.
You might check on that. I'm rather fearless about flashing Dells because they have a Clear-the-BIOS option on their motherboards, too. On these desktops, I'm sure this would be far handier to access than on notebooks.
Flashing BIOS can also be affected by add-in cards. If you've got a different video card, different sound-cards, wireless cards or, especially, controller cards to add SATA, IDE or USB ports - these can impact the motherboard's BIOS update abilities.