‘all the BIOS settings stored in your computer used to be stored in a CMOS memory.’
The windows clock is a software one & if the correct time is diplayed when you restart the computer, then you need to update the Windoz timing files.
I’ve also had this problem, and here is the URL to the page that tells what Microsoft has to say about it:
http://support.microsoft.com/support/kb/articles/Q189/7/06.ASP
It basically says that it could be a third-party anti-virus program or a screen saver causing the problem. I knew it couldn’t be the lithium battery in my case, because it was happening both at home and on my brand-new work computer. I think Norton AntiVirus is the culprit in my case, but I figured it would be better to have a slow clock than a virus-infected computer, so I decided to keep Norton running and just deal with it.