CMOS Reset

TABLE OF CONTENTS

• Symptoms
• Video Guide
• Written Guide

Symptoms

No POST (Power On Self Test)

No Video/Display

Other strange behaviour in many forms

Video Guide

Here is an example YouTube video showing the process. It is not our video and it's a little old but some people might find it easier to see someone doing it rather than reading a guide: https://youtu.be/Pdp_L5IxaNI?t=22 

Written Guide

A CMOS reset effectively resets your motherboards current settings to the manufacturer's default settings.

For this process, the system should be turned off and the power cable should be removed from the unit.

While looking at the front of your system please remove your left side panel, you can do this by removing the two screws at the back of the left side panel, one screw at the bottom and one at the top.

Locate the round CMOS battery (CR2032) which simply needs to be removed for 10 to 15 seconds before re-inserting it back into the slot.

To find this battery check your motherboard manual - either physical in the accessories box or you can find them on the manufacturer's website online. If you're struggling to find this please ask us and we'll find your motherboard and send a picture of the battery location.

Alternatively, you can use the CMOS jumper method. This is what our engineers typically use as it's quicker and easier than the battery method for us but there is a little higher risk associated if it's done wrong.

To start the process of resetting your CMOS please make sure that your system is powered down but the power should be left on at the Power Supply Switch (i.e. the system is on Standby). Again, open the side panel to get access to the internals.

You then need to locate the CMOS jumper on the motherboard and then make contact between the two pins next to the CLRTC or CLR_CMOS jumpers (depending on the brand).

To find this jumper check your motherboard manual - either physical in the accessories box or you can find them on the manufacturer's website online. If you're struggling to find this please ask us and we'll find your motherboard and send a picture of the jumper location.

You can make contact between these pins by using a pen or screwdriver, make sure that the object you are using is electrically conductive at the contact point with the pins and that it only touches the CMOS jumper metal pins. If you touch other areas you could short the motherboard.

(Older Motherboards) If there are three pins and there is a plastic jumper cover on two of the pins you need to move the jumper from pins 1-2 to 2-3 and back again after about 5 seconds.