ASSUME you mean the little coin sized battery?
I don't know what you mean by "back to factory settings",
but the answer is actually yes, and no.
NO, it won't make any changes to anything on your hard
drive or any programs you've installed or files you've
created or any changes you made.
YES, in the sense that, IFF you have made changes to what
is variously known as CMOS RAM. System Ram, etc., the
settings you access by F2, CTRL-ESC, whatever, during
bootup, it depends on the brand computer you have, you will
lose THOSE system settings, IFF you have changed them, and
they will simply go back to "default", usually, not always,
the settings the computer was delivered with.
Therefore, take the advice to go into your system
settings and write down what each one is, so if you need
to, you can put them back. Be sure to check each menu, and
do not change anything when you're there. Use ESC to back
your way out of the menues until you can press the button
that says "exit without saving changes".
IFF no one, not even you, has ever changed anything in
the system settings, or you don't know, you still want to
write them down, just in case the factory made changes to
them before sending you the computer.
Come on back if you need more help. Lots of other helpful
people here.
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