CMOS Battery - clock / Win 7

[hayate adil]

Hey guys, quick question :

 

When you shut down your pc and cut off power, the OS starts and thinks its the time you plugged out your power cable; after you've plugged it in again.

 

My Question is: If the CMOS Battery powers "Memory" to save the bios settings then why doesn't it just keep the clock going ?

 

Because my laptop doesn't stop its clock, when every power source but the CMOS battery is removed. (Yep I thought of the battery ^^)

 

Does anybody have an answer ?

 

THANKS !

[Osmium]

I would imagine the reason why not would be to not drain the battery or put any extra strain at all on it. I do not actually know the answer but that  is my best guess.