Dell OptiPlex 9010A System BIOS A10

Please turn off Bitlocker before flash BIOS install instruction.

Upgrading and Downgrading between Currently Released BIOS Images (Pre-Win8 Released BIOS) and Win8 Feature Enhanced BIOS Images (Win8 Released BIOS)

Upgrading:
The new Win8 Released BIOS contains new features and behavior, but the upgrade process for the end user is still unchanged. Simply run the EXE application normally and the BIOS will handle incorporating the new features and logic with your current settings. After the upgrade, you will immediately see that one of the visible changes is to the logo screen during boot, which only displays the logo at a larger size with no other information or text.

Downgrading:
Once a machine has a Win8 Released BIOS running on it, downgrading to a Pre-Win8 Released BIOS requires removing some unique functionality and security enhancements that are only present in a Win8 Released BIOS. This downgrade process described here is specific to Win8 Released BIOS to Pre-Win8 ReleasedBIOS transitions ONLY, and does not affect the normal rules/operations for downgrades of Pre-Win8 Released BIOS to an older Pre-Win8 Released BIOS, or Win8 Released BIOS to an older Win8 Released BIOS.
To install a Pre-Win8 Released BIOS on a machine running a Win8 Released BIOS, you will still use the same EXE application released for the BIOS version you wish to go to. When in Windows or DOS, your interaction with the application will be the same, but upon the machine restarting in order to do the update you will be prompted to accept the actions required in order to downgrade the machine and then prompted enter your admin password (if set). These prompts can not be accepted remotely and must be accepted by using an attached or built-in keyboard.
Due to compatibility of features, and ensuring platform stability, the only way to downgrade is to reset all the settings in the machine to a default factory state as if it had been shipped with a Pre-Win8 Released BIOS; specifically including defaulting the boot mode to Legacy (not UEFI), removing all passwords, and defaulting all user selectable settings. The following is retained on the machine (all other settings are reset): Windows Keys (if present), Service Tag, Asset Tag, Ownership Tag, Manufacturing Date, Ownership Date, and Express Service Code.
Downgrading is blocked if either Secure Boot is on or if Computrace has been activated. Due to security rules and protecting our machines from malicious attacks, if a user wishes to downgrade he/she must first ensure both of these are disabled or off. (Machines that are shipped out of the factory with Win8 Operating System are required to have Secure Boot initially on.)
After running the application, accepting the downgrading conditions prompts after restart, and the BIOS downgrading process is finished, the platform will be operating with the Pre-Win8 Released BIOS you desired. You may then go to the Firmware Setup to change settings and configure the machine as needed.