1. 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. Perhaps the CMOS clock is the problem.
Note: If the computer is a member of a domain, the computer clock is probably synchronized automatically by a network time server. If it is not a member of a domain, the computer's clock is automatically and regularly synchronized by an Internet time server. If you do not have a continuous Internet connection through a cable modem or DSL modem, the automatic synchronization might not always occur. In that case, you can force an immediate synchronization by clicking the Update Now button, which is not available unless the Automatically synchronize with an Internet time server check box is selected:
2. Click Start, Control Panel, Date, Time, Language, and Regional Options, and then click Regional and Language Options. On the Regional Options tab under Standards and formats, click Customize. On the Time tab, specify any changes wanted.
I set the time for 7:00 A.M. using options. However, when I bring up the auto update window is is showing 3:00 A.M. Which is it going to use? I'm not on line at 3:00 A.M.