I suggest that you review the information posted on the following article:
Specially the one that says "Computer will not boot after BIOS update" and "Downgrading the BIOS version".
If the issue persists, please provide full information on the hardware installed in your system (i.e.: processor, memory part number, etc) and full details on the behavior you see from the system.
you should not update bios unless you are having the symptoms indicated by the information listed on the bios update.
updating bios is required only for the problem indicated in the update. updating for no reason will give you problems almost every time.