How to Reset CMOS on a Dell Inspiron

By Chase Hasbrouck

Most computer motherboards, including those in the Dell Inspiron, contain a complementary metal-oxide-semiconductor (CMOS) battery. This battery powers the CMOS memory, which keeps the system clock running even when the computer is off. Occasionally, the CMOS memory can become corrupted, or the battery can fail. A simple battery pull or replacement can reset the CMOS memory, clearing any incorrect or faulty data.

Things You'll Need

  • Small Phillips screwdriver
  • Small slotted screwdriver or other pry tool
  • Replacement coin-cell battery (if desired)

Step 1

Turn the Inspiron off. Unplug all connectors and remove the battery.

Step 2

Open the display to its full extension so that it lies flat.

Step 3

Insert a pry tool underneath the right side of the hinge cover (between the keyboard and display) and gently pry the hinge cover loose.

Step 4

Unscrew the two screws located at the top of the keyboard. Lift the keyboard and disconnect the keyboard ribbon cable from the computer. Set the keyboard aside.

Step 5

Insert the pry tool underneath the battery and gently remove it. When removed, the CMOS automatically resets. If desired, insert a fresh battery.

Step 6

Reverse the previous steps for reassembly.

Tips & Warnings

  • Avoid electrostatic discharge damage to your computer by grounding yourself, using a grounding strap or by frequently touching a metal surface.