a battery in the computer
The CMOS contains user-defined settings for the BIOS. The Bios is a program that contains hardware instructions on how to start the computer.
CMOS settings are altered by the BIOS program while in setup mode.
Assuming you mean "flash the CMOS", when the CMOS settings are so messed up, you cannot access the BIOS.
Data stored in CMOS can be altered using a CMOS editor program. CMOS commonly stores the computer's BIOS and its content can be changed using the inbuilt BIOS settings utility.
You can press the Delete or F2 key to get into bios and then you can reset the settings or you can reset CMOS. This guide shows you how to reset CMOS - http://www.eteknix.com/how-s/how-reset-cmos-122/
There are three ways to clear the CMOS on a computer. You can access the BIOS menu and reset the BIOS settings, you can use the motherboard jumper or clear it by reseating the CMOS battery.
CMOS or BIOS configuration settings
Data stored in CMOS can be altered using a CMOS editor program. CMOS commonly stores the computer's BIOS and its content can be changed using the inbuilt BIOS settings utility.
To manage simple devices (system BIOS)To start the computer (startup BIOS)To change settings on the motherboard (CMOS setup).
cmos ram might be corrupt. run bios setup and reset bios to default settings. if it occurs again try, flashing bios.
CMOS Setup The BIOS is the name of the ROM Chip that holds all the data about how to start the computer up, and perform POST,Power On Self Test etc. And the CMOS was a software located on the BIOS Chip that enabled a UI for one to change the BIOS settings, ie like time, date, other settings.
If the CMOS battery dies you lose the settings that are held in the BIOS (Basic Input Output System). These include settings such as date/time, boot order,etc.