Simple Script To Check, if Client using Correct TimeSource

# Collecting All Active Directory server Information

$ADServers = (Get-ADForest).Domains | %{ Get-ADDomainController -Filter * -Server $_ } | Select-Object name -ExpandProperty name

# Checking Local time Source from Client Computer

$Windowstime = w32tm /query /source

# Took Only hostname from Windows Time

$ClientTimeSourceHostName=$Windowstime.Split(".")[0]

# Checking If Client having current AD Server as TimeSource.

If ($ClientTimeSourceHostName -in $ADServers){
Write-Host "Computer having correct time source"

}else{
Write-Host "Computer not Using Correct TimeSource"
}