ASRock.com Homepage
Forum Home Forum Home > Technical Support > Intel Motherboards
  New Posts New Posts RSS Feed - How to clear CMOS via battery removal
  FAQ FAQ  Forum Search Search  Events   Register Register  Login Login

Topic ClosedHow to clear CMOS via battery removal

 Post Reply Post Reply
Author
Message Reverse Sort Order
Xaltar View Drop Down
Moderator Group
Moderator Group
Avatar

Joined: 16 May 2015
Location: Europe
Status: Offline
Points: 24518
Direct Link To This Post Topic: How to clear CMOS via battery removal
    Posted: 12 Aug 2015 at 9:08pm
I have found myself giving the same advice in many threads so I have decided to place the information here. 

The clear CMOS jumper and reset factory defaults are not always effective in solving BIOS value corruption and so the only other recourse is to remove the CMOS battery. Many people are aware of this method but fairly often it is not done correctly and hence does not resolve the issue. Below I will outline a foolproof method to achieve a full CMOS clear.

1. Disconnect the system's power from the wall
2. Press and hold the power button for 10 seconds to be sure residual power is discharged
3. Place the "Clear CMOS" jumper in the clear position
4. Remove the CMOS battery
5. Leave the system in this state for 4 hours. 10 minutes is enough in most cases but if that yields no result then to be absolutely certain CMOS is clear I recommend 4 hours.
6. Place the "Clear CMOS" jumper back in its original position
7. Replace the CMOS battery
8. Power on the system

This method should effectively rule out BIOS value corruption as a culprit during troubleshooting. 

BIOS value corruption = corrupted settings in the BIOS
BIOS corruption = Corrupt BIOS/UEFI firmware due to a bad flash
Back to Top
 Post Reply Post Reply
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.04
Copyright ©2001-2021 Web Wiz Ltd.

This page was generated in 0.125 seconds.