Either battery or virus infection
Bios is Basic Input and
Output System, and the system
will check that the bios setting and the cmos memory/values are the
same during startup.
Once the system power down, ram and other temp storage device
will lose power(and thus memory), so the battery is there so that
there is some 'charge' or electric to store certain info/setting
and maybe the date and time, in the cmos
Thus if you have no batt, then the comp check and notice that
the values of the bios and cmos doesnt tally, and they will warn
you, that might be how the error came about
The battery that is on the motherboard is actaully those watch
batteries. Or the flat round ones that looks like a pancake
in your calculator
i think it is not very expensive
Unless of course your computer is those super duber old types
that requires desoldering, draining out the signal, then solder the
connection back in
