Are you seeing a 3-6 or 3-7 LED No POST diagnostic error on your OptiPlex, Alienware, XPS, Vostro, or Inspiron personal computer?
The following section of this article takes you through the steps that are required to use the integrated BIOS recovery facility. This facility aids you in recovering from a No POST issue on your system.
Affected systems:
This article takes you through how to perform BIOS recovery procedures. Either from the USB Key or the hard drive These are used once the BIOS has been corrupted and is reporting a startup issue such as a No POST error. (Such as the power LEDs blinking amber repeated in a pattern (3, 6) or (3, 7) during system boot.)
Remove the power cable from the affected computer.
On a working computer with Internet access, download the latest BIOS.exe:
Go to the Dell Support Site.
Enter the service tag or express service code of the affected personal computer to get drivers specific to how the system shipped.
Alternatively, you can choose the affected personal computer system type from the product list to get a general list of drivers for that system.
Click the Drivers & Downloads drawer in the menu.
Ensure you have the correct operating system set.
Select the BIOS drop-down category.
Look for the System Type BIOS Update Driver.
Click the Download button and follow the on-screen instructions to save the update file to a safe location on the working personal computer.
On the working system, click the Start Menu icon. Go to the CommandPrompt/PowerShell application. Right-click the icon to run the command-line application as an administrator. (You need administrator rights on the working system for this work properly.)
On your Windows Command-line application, go to the location you saved the BIOS update (that is cd c:\temp\) and type the following command to extract the recovery file:
C:\<downloaded BIOS file location>\<downloaded BIOS filename.exe> /writehdrfile /writeromfile
Rename the file from downloaded BIOS filename.hdr to BIOS_IMG.rcv.
Copy the recovery image file BIOS_IMG.rcv to the root directory of a bootable USB drive.
Plug the USB drive to the affected system.
Plug the power cable back into the affected personal computer.
When you power the system on, press and hold down the CTRL + ESC keys until the BIOS Recovery page appears. (If it cannot enter the BIOS Recovery page. Remove the power cable and CMOS battery coin and wait for about 1 min. Reseat the CMOS battery and then replug the power cable and reseat the CMOS battery and repeat step 9.)
Select the Recover BIOS option on the screen to perform a BIOS recovery.
The system shows a process bar of the BIOS Flashing Process. (It may take 1 minute to complete.)
Once the BIOS flash process is complete, it displays an on-screen message asking you to Press any key to reset the system.
Figure 4: BIOS Flash Complete Message
Follow these steps to format the USB drive as FAT32:
Plug the USB drive into a working personal computer.
Press the Windows + E key together to open the File Explorer application. (also known as Windows Explorer)
Right-click the applicable USB drive and click Format.
Change the File system to FAT32.
Check the box next to Quick Format.
Click Start to begin formatting the USB drive.
Remove the power cable from the affected personal computer.
Once a SATA or M.2 NVMe drive is replaced, you can reinstate the BIOS Recovery capability. Reinstitute the default configuration on the SATA hard drive or M.2 NVMe SSD:
Remove any newly added or replaced SATA hard drive or M.2 NVMe SSD from the system.
Reconnect the SATA hard drive or NVMe SSD that originally shipped with the unit.
Reconnect the power cable and power on the system. Wait for 20 to 30 seconds, for the system to boot into the BIOS recovery menu automatically.
Select the Recover BIOS then 'continue', 'confirm' on the screen to perform a BIOS recovery. (If the BIOS recovery file is illegible, the dialogue displays UNSUPPORTED on the screen, and go to recovery from USB)
Figure 1: Recover BIOS
Figure 2: Recover BIOS Screen for Inspiron 7700, Inspiron 5400, Inspiron 5401
Figure 3: The illegible Screen for Inspiron 7700, Inspiron 5400, Inspiron 5401
The system shows a process bar of the BIOS Flashing Process. (It may take 1 minute to complete.)
Once the BIOS flash process is complete, it displays an on-screen message asking you to Press any key to reset the system.
Figure 4: BIOS Flash Complete Message
Follow these steps to format the USB drive as FAT32:
Plug the USB drive into a working personal computer.
Press the Windows + E key together to open the File Explorer application. (also known as Windows Explorer)
Right-click the applicable USB drive and click Format.
Change the File system to FAT32.
Check the box next to Quick Format.
Click Start to begin formatting the USB drive.
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