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How to verify that the CMOS battery needs to replace

The CMOS battery is named after the Complementary Metal Oxide Semiconductor power. The CMOS has the current date and time functions for desktop and laptop computers. It allows the computer to automatically adjust the time, even on computers that are disconnected for long time. When a computer no longer has the date and time and forget it on every boot, the CMOS battery probably needs replacing. Some computers have messages when the battery is weak, while others just lose the current date and time after each shutdown.

Time & Date Errors

1. Turn on the computer. Look in the task bar at the bottom right. Make sure the date and time is set correctly. Double-click the time and click the up or down arrow to switch to the correct time. Click on the arrow next to month to change the month. Click "OK" when finished.

2. Turn off the computer. Wait 3 to 5 minutes and start the machine.

3. Look on the taskbar to see if time was lost and said a strange date January 1, 2000. Replace the CMOS battery, if this is the case.

CMOS Error Message

1. Look for error messages like "CMOS checksum error", "CMOS Read Error" or "CMOS battery failure" when you start your computer. These errors are caused in the machines shut down for several months or when the CMOS must be replaced.

2. Let the computer on for 24 hours. Restart the computer and find the error.

3. Change the CMOS as the return error.

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What is mean CMOS battery use for in computer motherboard ?

CMOS stands for Complementary Metal-Oxide Semiconductor. It is basically a chip in the mother board that stores information such as your system hardware settings and date and time. It is powered by a battery the size of a small coin. Without the CMOS battery, your computer will revert to original manufacture hard ware settings every time you turn on your computer. If you keep having to set the correct date and time of your computer every time you turn it on, then it's time to replace the CMOS battery. I hope that helps.

Nov 27, 2014 | Computers & Internet

1 Answer

cmos incorect perriferique non specifier

google translated

incorrect CMOS device not specify

CMOS device(electronics)

A device formed by the combination of a PMOS

(p-type-channel metal oxide semiconductor device) with an NMOS (n-type-channel metal oxide semiconductor device). Derived from complementary metal oxide semiconductor device.

The CMSOS is only a battery to store you're bios/mainboard settings.
CMOS is an on-board semiconductor chip powered by a CMOS battery inside computers that stores information such as the system time and date and the system hardware settings for your computer..

The moment that you unplug the power and remove the battery for at least 10seconds, the mainboard will reset it self into the 'default-state'.

This can also be done by selecting 'reset to default settings' in bios screen.

Restart your computer
During the boot process you will see on the screen to press a certain key to enter setup usually the Delete or F2 key
this will vary depending on your computer and operating system

Press and hold that key during the boot up process to enter BIOS using the arrow keys load failsafe defaults or load optimized defaults press escape then press f10 to save to cmos to restart

hope this helps

Oct 10, 2012 | Computers & Internet

2 Answers

what.s the useful of cmos in this board

CMOS Battery powers the real-time clock and CMOS memory, which retains all the BIOS Settings including date.


May 04, 2011 | Compaq (203966-001) Motherboard

1 Answer

My Laptop is Dellstudio15,When I swith on my laptop is showing error while booting it self is: Check date and time settings,System CMOS Checksum is Bad.Please help on this.

This error message means that its time for you to replace you CMOS battery.

CMOS battery is a small battery on the system board that provides power to the Complementary Metal Oxide Semiconductor (CMOS) chip, even while the computer is turned off. This chip contains information about the system configuration (e.g., hard disk type, floppy drive types, date and time, and the order in which the computer will look for bootable disks). The CMOS battery allows the CMOS to preserve these settings.

Hope this information willbe helpful. Thank you for using FIXYA.

Apr 13, 2011 | Computers & Internet

3 Answers

what is cmos

Complementary metal-oxide-semiconductor (CMOS) (pronounced /?si?m?s/) is a technology for constructing integrated circuits. CMOS technology is used in microprocessors, microcontrollers, static RAM, and other digital logic circuits.

Oct 30, 2010 | Acer Computers & Internet

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