Recovering The Operating System; Flashing Bios (Usb Key); Flashing The Bios - Dell OptiPlex 7490 All-In-One Service Manual

Table 21. Diagnostic LED behavior (continued)
Blinking pattern
Amber
3 4
3 5
3 6
3 7
4 1
4 2

Recovering the operating system

When your computer is unable to boot to the operating system even after repeated attempts, it automatically starts Dell
SupportAssist OS Recovery.
Dell SupportAssist OS Recovery is a standalone tool that is preinstalled in all Dell computers installed with Windows 10 operating
system. It consists of tools to diagnose and troubleshoot issues that may occur before your computer boots to the operating
system. It enables you to diagnose hardware issues, repair your computer, back up your files, or restore your computer to its
factory state.
You can also download it from the Dell Support website to troubleshoot and fix your computer when it fails to boot into their
primary operating system due to software or hardware failures.
For more information about the Dell SupportAssist OS Recovery, see Dell SupportAssist OS Recovery User's Guide at
www.dell.com/support.

Flashing BIOS (USB key)

Steps
1. Follow the procedure from step 1 to step 7 in
2. Create a bootable USB drive. For more information see the knowledge base article
3. Copy the BIOS setup program file to the bootable USB drive.
4. Connect the bootable USB drive to the computer that needs the BIOS update.
5. Restart the computer and press F12 when the Dell logo is displayed on the screen.
6. Boot to the USB drive from the One Time Boot Menu.
7. Type the BIOS setup program filename and press Enter.
8. The BIOS Update Utility appears. Follow the instructions on the screen to complete the BIOS update.

Flashing the BIOS

About this task
You may need to flash (update) the BIOS when an update is available or when you replace the system board.
Follow these steps to flash the BIOS:
104 Troubleshooting
White
Recovery image found but invalid
Power-rail failure
System BIOS Flash incomplete
Management Engine (ME) error
Memory DIMM power rail failure
CPU power cable connection issue
"Flashing the
Problem description
BIOS" to download the latest BIOS setup program file.
Suggested resolution
Flash the latest BIOS version. If problem
continues, replace the system board.
EC ran into power sequencing failure. If
problem continues, replace the system
board.
Flash corruption detected by BIOS. If
problem continues, replace the system
board.
Timeout error displayed while waiting on
ME to reply to HECI message. If problem
continues, replace the system board.
Replace the system board.
Initiate PSU BIST. If problem persists,
replace the system board.
000145519 at www.dell.com/support.