The Time and Date in my PC change once I switch it off, Why??

Tweet

The time and date in my Pc change once i switch it off. The next time i turn it on i get a page saying that -CMOS wrong settings, date and time are set wrong. Then it gives an option to press f2 for running the setup and changing the time and date, and the second option is pressing f1 and continue without making the changes in the time and date. I tried both. When i pressed f2, i entered the setup and updated the date and time,but next time when i switched on the PC, i again got the abovesaid page. So problem not solved. Secondly, when i pressed f1 and chose to continue without changing the time and date, i updated it, when i logged in, in my id. But then again again when i logged in, in my PC, I found it was again wrong, and got the abovesaid page in the beginning. And this wrong date and time which i get is 12.00 am, 16th february 2004!! I get this time and date whenever i start the PC. Now what shall I do, i've tried updating the time/date in setup, i've tried doing it on my desktop, but the problem still persists. Even i changed the battery in my CPU, but there was no change! Kindly guide me...