A dead battery is the only thing I can think of that would reset the system clock each time that it is rebooted.
Just because you bought the computer three to four years ago doesn't mean the battery didn't sit around on a shelf waiting to be installed in the computer. Also, there may have been a manufacturing defect in the battery that caused it to lose charge over time.
Don't waste your time wondering why - replace the battery and get on with your computer using happiness! :-)
I hope this helps!
davidchilders
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I sync my clock with NTP (network time protocol) servers on the internet, such as are provided by various governmental services (NIST, etc). That way, even if the clock battery is fubar, my system still keeps proper time.
rubberman
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