how often does time sync
If your system is standalone, the default sync interval for system time is 604800 seconds (7 days). If you are in a domain environment, the default sync interval is 3600 seconds (0.04166667 days). If you are using XP Pro, you can adjust your settings using Group Policy editor (GPedit - Administrative Templates\System\Windows Time Service\Time Providers) or you can adjust things through a registry edit (works for any version of XP).