How to Perform a BIOS or CMOS Reset and Clear the NVRAM on Dell Computers

Table of Contents:

1. Introduction
2. How to reset the BIOS from the BIOS interface
3. How to clear the BIOS, CMOS, or NVRAM using a jumper on a desktop computer
4. How to clear the BIOS, CMOS, or NVRAM by reseating the CMOS battery
5. How to clear the BIOS, CMOS, or NVRAM on Desktop computers without an RTCRST Jumper or serviceable Coin Cell battery

Introduction

The information stored in the BIOS, known as the Extended System Configuration Data (ESCD), can occasionally become corrupt due to various reasons. These reasons include power events, incorrect settings, hardware incompatibility due to a specific setting, or a Power-on self-test (POST) or video problem. In these cases, it is sometimes necessary to reset the BIOS or CMOS to factory default settings. In other circumstances, clear the NVRAM or perform a Real-Time-Clock (RTC) Reset operation.

How to reset the BIOS from the BIOS interface

1. Turn on the computer.
2. Tap the F2 key several times until Entering Setup appears.
3. Reset the BIOS to factory defaults. The method to reset the BIOS varies between different computers:
   • Click the Load defaults button.
   • Press the F9 key to load the default settings.
   • Press the Alt + F keys to load the default settings.
4. Press the Esc key and select Save and exit or Exit.
5. Press the Enter key to save all changes and exit the BIOS setup screen.
6. The computer restarts and boots to the operating system.

How to clear the BIOS, CMOS, or NVRAM using a jumper on a desktop computer

The RTCRST jumper helps reset or clear the NVRAM on the computer. The ESCD information that is contained in the NVRAM can be cleared by following the steps that are mentioned below. The NVRAM is cleared when the jumper is set to the closed position and turning on the computer for 10 seconds.

1. Before you begin, follow the: Safety Precautions When Working with Electronic and Electrical Equipment
2. Turn off the computer and disconnect the power cable from the computer.
3. Remove the computer cover. For model-specific information, see the User Manual of your desktop.
4. Locate the 2-pin password jumper labeled PSWD on the motherboard.
5. Remove the 2-pin jumper plug.
6. Locate the 2-pin CMOS jumper labeled RTCRST on the motherboard.
7. Move the 2-pin jumper plug from the password jumper to the pins on the CMOS jumper.
8. Plug the power cable to the computer and wait for 10 seconds for the CMOS to clear.
9. Disconnect the power cable from the computer.
10. Move the 2-pin jumper plug back to the password jumper.
11. Replace the computer cover. For model-specific information, see the User Manual of your desktop.
12. Connect the power cable to the computer and turn on the computer.

How to clear the BIOS, CMOS, or NVRAM by reseating the CMOS battery

The BIOS can be reset to factory defaults by reseating the CMOS battery that is connected to the motherboard. This process is applicable for both Dell desktops and laptops. Follow these steps if the PSWD or RTCRST jumpers are not accessible on a Dell desktop or if you are using a Dell laptop.

1. Before you begin, follow the: Safety Precautions When Working with Electronic and Electrical Equipment
2. Turn off the computer and disconnect the power cable from the computer.
3. If you are using a Dell laptop, disconnect the battery from the computer. For model-specific information, see the User Manual of your computer. If your Dell laptop has a nonremovable battery, see the Dell knowledge base article: How to Reset the Real-Time Clock (RTC) to Recover Your Dell Laptop
4. Remove the computer cover. For model-specific information, see the User Manual of your computer.
5. Locate the CMOS coin-cell battery (Figure 2 and 3).
6. Carefully, disconnect the coin-cell battery from the motherboard.
7. Press and hold the power button for 10-20 seconds to drain residual power.
8. Connect the coin-cell battery to the motherboard.
9. Close the computer cover.
10. Connect the battery and the power cable to the computer.
11. Turn on the computer.
12. A warning message appears indicating that the date and time is not set.
13. Press the F2 key to enter the BIOS screen.
14. Set the date and time according to your time zone.
15. Save and exit out of the BIOS screen.

How to clear the BIOS, CMOS, or NVRAM on Desktop computers without an RTCRST Jumper or serviceable Coin Cell battery

If your desktop computer was produced before April 2020, the computer most likely has a jumper-based reset. Desktop computers manufactured after April 2020 use the RTC Reset ability.

For desktop computers that use RTC Reset, hold the power button for 30 seconds.

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Recommended Articles

Here are some recommended articles related to this topic that might be of interest to you.

• Dell BIOS Updates
• How to Restore the BIOS or UEFI (System Setup) to Factory Defaults on a Dell Computer
• How to Recover the BIOS on a Dell Computer or Tablet
• How to Reset or Clear the BIOS Password
• How to use the jumper to reset the BIOS password on your Dell desktop computer
• How to Replace a CMOS (coin-cell) Battery on Your Dell Desktop
• Resetting the BIOS to Default Configuration on a System May Not Match the BIOS Settings Configured from the Factory
• How to Replace a CMOS (Coin-Cell) Battery on Your Dell Notebook
• Dell Client Products Unauthorized BIOS Password Reset Tools
• How to Reset the Real-Time Clock (RTC) to Recover Your Dell Desktop System
• Resolve No Power, No POST, No Boot or No Video issues with your Dell Computer
• How to Reset the Real-Time Clock (RTC) to Recover Your Dell Laptop
• Factory Reset, Restore, or Reinstall Microsoft Windows on a Dell computer

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