Your CMOS battery may be dying.
I noticed this morning that my time was wrong and the date had changed back to Sept 2001. I corrected it. Just curious as to what caused this to happen.
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I noticed this morning that my time was wrong and the date had changed back to Sept 2001. I corrected it. Just curious as to what caused this to happen.
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1. Computers keep the time on their internal clocks, which allows them to perform any function that requires the date or time. For scheduling purposes, the clocks should be set to the correct date and time synchronized other clocks in a network when applicable. Otherwise, the date and time must be set manually. If your computer is not a member of a domain/workgroup, configure the date and time manually and don't worry about it.
2. A computer actually maintains three separate clocks:
a. The Real Time Clock (RTC) is physically located on the system board (motherboard) and powered by the CMOS battery so it is consistently updated even if the system is not receiving AC power.
c. The CMOS Clock is a logical clock stored in the BIOS chip on the system board. Its settings are maintained (but not updated) in non-volatile RAM while the system is powered off.
d. The Operating System (OS) Clock is a logical clock/"time set" in system memory when the system is powered on. When a computer is turned on, the CMOS clock synchronizes with the RTC during the POST (Power On Self Test) operation. When the operating system boots, it reads the current time from the CMOS clock and maintains its own independent time keeping piece. The OS clock does not synchronize again with the CMOS clock unless the OS clock is manually changed (at which time both the CMOS clock and RTC are set to the time stored in the OS clock), or the system is rebooted.
Auggie, the desktop batteries are easy to replace. If your computer has some age then its worth checking. Open the case and locate the batteries. They can be anything from AA batteries to the round flat nickle shaped ones. Mine is located attached to the motherboard.
Good luck!... and stay on time.![]()
Glenn