Disable Time Synchronization
This feature disables / enables the Windows Time (W32Time) service.
Check mark is set - the service is disabled, check mark is removed - the service is enabled.
Disabling the Windows Time service saves system resources.
Description of the Windows Time service from Microsoft, in Windows XP:
"Maintains date and time synchronization on all clients and servers in the network. If this service is stopped, date and time synchronization will be unavailable. If this service is disabled, any services that explicitly depend on it will fail to start."
System reboot: not required
OS: XP, Vista