When was SQL Server restarted?
Mohammad Nizamuddin provides 4 different queries to find when the server was started, the first login occurred, the tempdbs were created.
--SELECT sqlserver_start_time FROM sys.dm_os_sys_info; --I didn't have permissions for this one
SELECT login_time FROM sys.dm_exec_sessions WHERE session_id = 1; --this returned nothing for session_id = 1, for me
SELECT crdate FROM master..sysdatabases WHERE name='tempdb' ;
SELECT create_date FROM sys.databases WHERE name = 'tempdb' ;
--select start_time from sys.traces where is_default = 1 ; --I didn't have permissions for this one