How do I reset the CMOS on my PC?

Whether it be due to your PC not wanting to start, a stuck error message, or your PC not wanting to start after a recent hardware change you may find yourself in a situation where clearing the CMOS settings may be necessary in order to get your system back up and running.  In this guide, we’ll be going over a few common methods for clearing the CMOS on your PC.

Preparing to Clear CMOS

To prepare your PC to clear the CMOS, you’ll need to start by shutting down the PC and either turn off the power supply (setting the switch to the O position) or unplug the power cable from the PC to ensure there is no power being fed to the PC.  From here, hold the power button on top of the PC for 20-30 seconds to make sure any remaining power in the system is drained before moving forward.

With the power completely drained from the PC, it’s time to find which method(s) are available to us to clear the CMOS.  Depending on your motherboard, you’ll have one of three options generally available:

Clear CMOS Button

Some models of motherboard may feature an easy to access "CLR_CMOS" or similarly named button.  These are generally located on the rear I/O of most boards as shown above with the NZXT N7 B650E, however some motherboards may have them located somewhere on the main body of the motherboard itself. 

To use the button, simply press and hold the button for 15-30 seconds with the PC completely powered off, then release the button and try starting the PC normally.

Tripping the CMOS Jumper pins

One of the most common ways to clear the CMOS is to trip a pair of CMOS jumper pins.  These pins may have a number of different names, but some common ones include:

• RESET_BIOS
• CLR_CMOS
• CLEAR_CMOS
• CLR_BIOS
• JBAT1

Once you have located the jumper pins, use a conductive object to create a bridge between the two pins.  This can be either a jumper that may be included with the motherboard or the tip of a screwdriver or house key.  So long as the item is metal and able to conduct electricity, you should be able to use it to bridge the pins.

Keep the pins bridged for at least 15-30 seconds before removing the bridge and starting the PC again.

Removing the CMOS Battery

The most commonly used way to clear the CMOS on your system is to remove the CMOS battery.  In order to retain settings, the CMOS must be constantly powered via a battery with the most common being a CR2032 button cell battery located somewhere on the motherboard.  In the case of many NZXT motherboards, this will be below the first PCI Express slot.

Most CMOS batteries will be held in using a simple spring-latch that hold the battery in place.  To remove the battery, simply compress the spring latch from the inside of the battery socket into the square cut-out as shown below.  Once compressed, the battery should lift on one side and be easily removable.

If you are having difficulty compressing the latch with your finger, you can use the end of a pen or screwdriver to make this easier.

To make sure that the CMOS is completely cleared, allow the PC to sit without the battery for at least one minute, with up to 5 or 10 minutes being ideal.  Once the time has passed, re-install the battery onto the motherboard with the positive side (generally this will have the battery text printed on it) facing you.

In some cases, you may find that the battery is mounted in a different way such as a vertical mount or it may be connected to a wire (this is more common on ITX form factor motherboards).  In these situations, please refer to the motherboard user's manual for how to remove this type of battery.

If you have any further questions, feel free to reach out to our Customer Support team.