$ChassiType = (gwmi Win32_SystemEnclosure).ChassisTypes
$Nics = Get-WmiObject Win32_NetworkAdapterConfiguration
foreach ($Nic in $Nics) {
    write-host $Nic
    if ($Nic.macaddress) {
        $MACAddress = $Nic.macaddress
        }


}
$tsenv = New-Object -COMObject Microsoft.SMS.TSEnvironment
$newPCName = $MACAddress -replace ':',''
$SN = gwmi win32_bios | Select –ExpandProperty SerialNumber
$paddedSN = $SN.padleft((12-$SN.lenght),"0")


switch ($ChassiType){
    {"3","4","6","7","13" -contains $_} {
    #desktops
    $OSDComputerName = "DSK" + $newPCName
    $tsenv.Value("OSDComputerName") = $OSDComputerName
    }
    default{
    $OSDComputerName = "LAP" + $paddedSN
    $tsenv.Value("OSDComputerName") = $OSDComputerName
    }
}