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Driver Details

Dell OptiPlex System BIOS, A04
OptiPlex SX280 A04 System BIOS
Release Date 2/21/2005
Importance: Optional
Version: A04

The following formats are available for the file you have selected

File Format: Windows/DOS Download File Download File
File Name:


Description: This file format consists of a BIOS executable file. The Universal (Windows/MS DOS) format can be used to install from Windows XP, Windows 2000, NT, Windows 9X, Windows ME or a MS DOS environment.
Download Type: HTTP
File Size: 525KB

Previous Versions

No previous version available.


OptiPlex SX280 A04 System BIOS

Level of Importance:Optional

Dell recommends the customer review specifics about the update to determine if it applies to your system. The update contains changes that impact only certain configurations, or provides new features that may/may not apply to your environment.


OptiPlex SX280
Operating Systems

Applies to

  • Dell Device

Fixes & Enhancements

The following changes have been made to BIOS rev A02 to create A04: 1. Add support for hard drives less than 528M in size. 2. Improve Asset Tag functionality. 3. Add support for newer microprocessors. 4. Updated VBIOS. 5. Improve memory detection code. 6. Improve PATA detection.

Installation instructions

Installation Instructions for the Universal (Windows/MS DOS) format

  1. Download file to Desktop
  2. Use one of the methods below to flash the Bios.

Download file to Desktop
The file SX280A04.EXE is using the Universal (Windows/MS DOS) format and is designed to be directly executed from Windows environment.
  1. Click Download now.
    The Export Compliance Agreement appears.
  2. Read the Export Compliance Agreement.
  3. If you agree, click to select I agree..
    The File Download window appears.
  4. Click the Save button.
    The Save As window appears.
  5. Select Desktop using the drop-down menu to the right of Save in.
  6. Click the Save button.
    A progress meter moves as the download is completed.
  7. 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.
Run the BIOS update utility from Windows environment
  1. Double click the Icon on your desktop labeled SX280A04.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.
Run the BIOS update utility from MS DOS environment (Non-Windows users)

NOTE: You will need to provide a bootable DOS diskette. This executable file does not create the MS DOS system files.
  1. Copy the file SX280A04.EXE to a bootable floppy.
  2. Boot from the floppy to the MS DOS prompt.
  3. Run the file by typing Y:\SX280A04.EXE (where y is the drive letter where the executable is located).


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This is an optional process and is not required for the downloading and installation of device drivers from this site.
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