cmos

i have a very basic question, at least i think. what exactly is cmos? is it like the bios? and secondly is it possible to lower my vcore in cmos, b/c i want to lower my vcore below stock settings as my mobo is messed up and is putting my vcore at 1.79 when i set it at 1.75 in bios.

o yeah the mobo is a7v333, not the system in my sig

CMOS stands for Complimentary Metal Oxide Semiconductor, basically the technical name for the memory chip. That chip is a battery powered backup memory chip that saves the system configuration settings for your computer.
The BIOS chip contains the Basic Input Output System settings for your system. It is a flash memory chip, reprogrammable by the use of high voltage to burn the new settings into the chip. It is the source of the basic CMOS configurations.

When you clear CMOS, on start up your computer will go back to the basic sysetm settings stored in the BIOS chip.