Do not turn off your computer or disconnect from the power source while updating the BIOS as this could harm your computer. During the update, your computer will restart and you may briefly see a black screen.

Before updating, please read the installation instructions and important information noted below.

Dell OptiPlex 990 System BIOS, A06

AUTO INSTALLED This file was automatically installed as part of a recent update. If you are experiencing any issues, you can manually download and reinstall.
OptiPlex 990 System BIOS

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Fixes & Enhancements

Defects Fixed:
1. Fix Forced Boot to CD support for Sandybridge UMA Platforms
2. Correct INT13 handler for ATA mode when system is under virtual x86 mode
3. DF477841: All 250GB drives show as 249GB in the BIOS.
4. DF479402: [REC LT] HDD slow performance with POINTSEC software installed
5. Pink Panther: Fixed Blinking Cursor Issue.
6. Fixed USB handoff sequence broken
7. DF476106: KG:UUT easily hang if write data and save on Hitachi HDD under DOS w/ AHCI mode.
8. DF480677: Can't boot to HDD attached to SCU if SATA ODD attached
9. DF463483: B/LSN:Auto reboot when booting to USB unbootable ODD from Boot Menu
10. DF477727: B/LSN:MEBx still can be entered by pressing Ctrl-P during POST after ME disabled
11. DF470840:BS:USB Key can't boot to DRMK with SAS HDD attached
12. DF476090: After disable NIC in BIOS menu, the BIOS menu will show wrong MAC address
13 DF462270: fixed that No SATA device BSOD in Win PE by intel recommend
1. CR468958: Create and Define SMBIOS Token to manage Control WLAN/WWAN Radio
2. Pink Panther: Update Gpe Orom 1.02.
3. Update to latest Intel microcode patch (MOB_P_10)
4. Support KillTPM feature and token.
5. Added Signed Firmware Update Transition BIOS.
6. CR484081:Pink Panther: System set to ATA or AHCI mode prompts message on every boot
7. CR485006:Pink Panther: Cato board SSVID and SSID values are zero
8. Updated Intel System Agent reference code to 1.2.0
9. Updated Intel PCH Reference Code to 1.2
10. Updated Intel PPM Reference Code to v1.2.1.1
11. Set KEY_TRANSITION_RELEASE to "0" for digital sign
12. BBSManager issue (it will cause ePSA to hang with >= 4GB RAM installed on B/LS/N)
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A06, A06

Release date

14 Sept 2011

Download Type

System BIOS




Dell Technologies recommends reviewing this update to determine if it applies to your system. The update contains changes that impact only certain configurations or provides new features that may or may not apply to your environment.
Available formats

File Format: Flash BIOS executable
File Name: O990-A06.exe
File Size: 5.43 MB
This is a large file. Depending on your connection speed, it may take some time to download.
Format Description:
This file format consists of a BIOS-executable file. To use it, download the file and copy it to a DOS-bootable USB flash drive, then boot the system to the USB flash drive and run the program.
To ensure the integrity of your download, please verify the checksum value.
Not available
Not available

By downloading, you accept the terms of the Dell Software License Agreement.

Additional details

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Dell Optiplex 990
Installation Instructions

The file O990-A06.exe is using the Hard Drive format and is designed to be directly executed from Windows environments.

    1. Click Download now.
      The File Download window appears.

    2. Click the Save button.
      The Save As window appears.

    3. Select Desktop using the drop-down menu to the right of Save in.

    4. Click the Save button.
      A progress meter moves as the download is completed.

    5. If necessary, click X in the upper right-hand corner of the Download Progress Window to close it upon completion.

    NOTE:Shut down all other applications prior to running the BIOS update utility. The update utility reboots your system in order to get the new BIOS loaded.

    1. Double click the Icon on your desktop labeled O990-A06.exe.

      The Dell Bios Flash window appears

    2. Click the Continue button.

      The message Pressing OK will close all applications, shut down Windows, Flash the BIOS, then reboot. appears.

    3. Click the OK button.

      The system will restart and the Bios Flash will be completed.

Need help with BIOS issues?

Find a solution in Dell's BIOS troubleshooting and usage guide.

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