Clock Synchronization Windows xpPro

You need an internet connection or a connection to a good NTP (Network Time Protocol) server which will correctly sync the clock. If you do have an internet connection then check properties of Time and Date control panel and click on 'Internet Time' and choose a local NTP server.

Otherwise you need a modem to connect to an Atomic clock:
http://www.worldtimeserver.com/atomic-clock/

If those PCs connect to a Windows 2000 Server domain, and they logon to that domain, they get the server's time, so the two PCs will be in Sync. If you also need the time to be exact real-time, you will either need your server to get the time from an ntp server or with another exact time source (like explained above). There are clocks that connect to a serial interface of PCs and those clocks are sychronized by a wireless signal from a special service provider.

This article will explain configuring the Windows Time Service on those PC's:

http://www.windowsnetworking.com/articles_tutorials/Configuring-Windows-Time-Service.html

As was stated earlier, in an AD forest, all time is synched by the forest-root domain PDC.

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