1) NO. Not required.
*If you heard about BIOS updates related to video cards it may have been referring to the vBIOS on newer cards to be upgraded to work with modern UEFI boards. Some UEFI cards have issues with older motherboards but I doubt the one you chose does. In those cases there's no fix anyway.
2) In general, do NOT update your BIOS. As said a failed flash can ruin the motherboard. If you have not observed any stability issues (BSOD or freezing) or conflicts (i.e. SSD doesn't seem to work) then I wouldn't bother.
3) You can look at the BIOS updates as well. Some are vague with "stability updates" but some are more specific. For example the last BIOS update for you was to address an issue with the FX-8320 CPU.
An earlier...