Time synchronization across a domain is important for Kerberos authentication. Authentication issues means potential issues with file shares, logons etc, not good stuff. Active directory handles time sync by ensuring all domain-joined computers sync their time with a domain controller and all domain controllers sync with the domain controller which has the PDC role.
Other than time synchronization being important, time accuracy is also important. If all of your computers sync with your PDC but your PDC time is incorrect this can also cause problems. Problems include authentication issues with non domain syncing devices and logging accuracy.
The following command will sync the local server with 'pool.ntp.org' .
w32tm /config /manualpeerlist:pool.ntp.org /syncfromflags:manual /reliable:yes /updatew32tm /config /manualpeerlist:pool.ntp.org /syncfromflags:manual /reliable:yes /update
Once your PDC is syncing time with an external source you can run this command to sync right away.
You can also run the command on client computers manually or in a batch file if you don't want to wait for the next time sync interval. Still having time sync issues or do you have a server refusing to sync it's time? Check out Network Share Not Accessible: Server’s Clock is Not Synchronized.