You can execute the below script to identify the optimal MAX DOP setting and set the MAX DOP as using SP_Configure procedure.
select case when cpu_count / hyperthread_ratio > 8 then 8 else cpu_count / hyperthread_ratio end as optimal_maxdop_setting from sys.dm_os_sys_info; -- Script to set the maxDOP sp_configure 'show advanced options', 1; GO RECONFIGURE WITH OVERRIDE; GO sp_configure 'max degree of parallelism', <OutPut of the above script>; GO RECONFIGURE WITH OVERRIDE; GO