Dell Precision 3590/3591 and Latitude 5550 System BIOS

Restart required

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.

Driver Id : NK0NG

Importance : Critical

Version : 1.21.0, 1.21.0 Latest version Recommended version Latest and Recommended version

Release Date : 15 Apr 2026

Download Type : System BIOS

Category : BIOS

This package contains the Dell system BIOS update. BIOS is a firmware package that is embedded on a small memory chip on the system board. It controls the keyboard, monitor, disk drives, and other devices. This update addresses the Dell Security Advisories (DSA). A security advisory is a statement when a security vulnerability impacts a product, and a remedy is available for the vulnerability.

Download Files

File Format: This file format consists of a BIOS executable file. The Universal (Windows/MS DOS) format can be used to install from any Windows or MS DOS environment.

File Name: Precision_3590_3591_Latitude_5550_1.21.0.exe

File size: 50.53 MB

To ensure the integrity of your download, please verify the checksum value.

MD5: 0611ef8331f7144ea3d0611ac9a9edf2

SHA1: 8a4e258984700e0660185f3d71ecd97f6a37f552

SHA-256: e00091e6569ad566f2d2d5707e3ee7ddbfc0add7d50033b3eacfc42373159601

Download .EXE

File Format: This file format consists of a BIOS Recovery image file. This file is used for the System BIOS Recovery process to recover a system from a corrupted BIOS.

File Name: BIOS_IMG.rcv

File size: 50.53 MB

To ensure the integrity of your download, please verify the checksum value.

MD5: 0611ef8331f7144ea3d0611ac9a9edf2

SHA1: 8a4e258984700e0660185f3d71ecd97f6a37f552

SHA-256: e00091e6569ad566f2d2d5707e3ee7ddbfc0add7d50033b3eacfc42373159601

Download .RCV

Fixes & Enhancements

Fixes:
- This release contains security updates as disclosed in the Dell Security Advisory DSA-2026-089. The DSA details are published on the Security Advisories, Notices, and Resources page, once they are publicly available. For more information about the release schedule, see Dell Client Drivers and Downloads Update Release Schedule.
- Fixed the issue where the IPV4 device is not displayed at the top of the Boot Sequence in the BIOS Setup.
- Fixed the issue where the Pass Through MAC Address is displayed incorrectly in the Command Line. This issue occurs when the system is connected to the Dell SD25 or SD25TB5 dock.

Enhancements:
- Updated the firmware version to align with the version in the Intel best-known configuration.

Important Information

- This BIOS contains the new 2023 Secure Boot Certificates.
- Once the BIOS is upgraded to version 1.20.0 or later, you cannot downgrade the BIOS to earlier versions. BIOS downgrades are restricted when there are security updates and important fixes with earlier versions that impact the functionality of the system.
- BIOS updates take no more than 5 minutes to be installed on your system. You can install the updates in the background while using the system.

Compatible Systems

Latitude 5550

Mobile Precision 3591

Precision 3590

Installation instructions

Updating the BIOS from Windows

Note 1: Before updating the BIOS, ensure that you suspend BitLocker encryption on a BitLocker-enabled system. If BitLocker is not enabled on your system, you can ignore this step. For information about how to disable BitLocker, see How to Enable or Disable BitLocker with TPM in Windows at support.dell.com.
Note 2: Do not turn off power or interrupt the BIOS update process during the update.
Note 3: Your system requires a restart after installing the BIOS. The restart can be deferred but must be completed to ensure that the update is installed.

Download and Installation
1. Click Download File.
2. Click Save to save the file to your hard drive.
3. Browse to the location where you downloaded the file.
4. Double-click the new file.
The system restarts automatically and updates the BIOS at the system startup screen. After the BIOS update is complete, system restarts again.