Server CPU utilization last 256 min

DECLARE @ts_now bigint = (SELECT cpu_ticks/(cpu_ticks/ms_ticks) FROM sys.dm_os_sys_info WITH (NOLOCK)); 

SELECT TOP(256) SQLProcessUtilization AS [SQL Server Process CPU Utilization], 
               SystemIdle AS [System Idle Process], 
               100 - SystemIdle - SQLProcessUtilization AS [Other Process CPU Utilization], 
               DATEADD(ms, -1 * (@ts_now - [timestamp]), GETDATE()) AS [Event Time] 
FROM (SELECT record.value('(./Record/@id)[1]', 'int') AS record_id, 
			record.value('(./Record/SchedulerMonitorEvent/SystemHealth/SystemIdle)[1]', 'int') 
			AS [SystemIdle], 
			record.value('(./Record/SchedulerMonitorEvent/SystemHealth/ProcessUtilization)[1]', 'int') 
			AS [SQLProcessUtilization], [timestamp] 
	  FROM (SELECT [timestamp], CONVERT(xml, record) AS [record] 
			FROM sys.dm_os_ring_buffers WITH (NOLOCK)
			WHERE ring_buffer_type = N'RING_BUFFER_SCHEDULER_MONITOR' 
			AND record LIKE N'%%') AS x) AS y 
ORDER BY record_id DESC OPTION (RECOMPILE);

MAX and AVG CPU utilization last 256 min

DECLARE @ts_now bigint = (SELECT cpu_ticks/(cpu_ticks/ms_ticks) FROM sys.dm_os_sys_info WITH (NOLOCK)); 

SELECT max(SQLProcessUtilization) AS [Max SQL Server Process CPU Utilization], 
	   AVG(SQLProcessUtilization) AS [Avg SQL Server Process CPU Utilization]          
FROM (SELECT record.value('(./Record/@id)[1]', 'int') AS record_id, 
			record.value('(./Record/SchedulerMonitorEvent/SystemHealth/SystemIdle)[1]', 'int') 
			AS [SystemIdle], 
			record.value('(./Record/SchedulerMonitorEvent/SystemHealth/ProcessUtilization)[1]', 'int') 
			AS [SQLProcessUtilization], [timestamp] 
	  FROM (SELECT [timestamp], CONVERT(xml, record) AS [record] 
			FROM sys.dm_os_ring_buffers WITH (NOLOCK)
			WHERE ring_buffer_type = N'RING_BUFFER_SCHEDULER_MONITOR' 
			AND record LIKE N'%%') AS x) AS y 
OPTION (RECOMPILE);

CPU utilization for each DB

WITH DB_CPU_Stats
AS
(SELECT pa.DatabaseID, DB_Name(pa.DatabaseID) AS [Database Name], SUM(qs.total_worker_time/1000) AS [CPU_Time_Ms]
 FROM sys.dm_exec_query_stats AS qs WITH (NOLOCK)
 CROSS APPLY (SELECT CONVERT(int, value) AS [DatabaseID] 
              FROM sys.dm_exec_plan_attributes(qs.plan_handle)
              WHERE attribute = N'dbid') AS pa
 GROUP BY DatabaseID)
SELECT ROW_NUMBER() OVER(ORDER BY [CPU_Time_Ms] DESC) AS [CPU Rank],
       [Database Name], [CPU_Time_Ms] AS [CPU Time (ms)], 
       CAST([CPU_Time_Ms] * 1.0 / SUM([CPU_Time_Ms]) OVER() * 100.0 AS DECIMAL(5, 2)) AS [CPU Percent]
FROM DB_CPU_Stats
WHERE DatabaseID <> 32767 -- ResourceDB
ORDER BY [CPU Rank] OPTION (RECOMPILE);