This script helps you find out the start time or the last restart time (it's up to you on how to call) of your SQL Server instance.

You can use anyone of the 3 statements provided below in your SQL Server instance that you want to find out the start time.

 

SQL
Edit|Remove
SELECT sqlserver_start_time FROM sys.dm_os_sys_info; 
 
SELECT login_time FROM sys.dm_exec_sessions WHERE session_id = 1; 
 
SELECT create_date FROM sys.databases WHERE name = 'tempdb';
 The output will be something like this:
If you have any suggestions, critics or need some help please leave a comment.
Hope it helps you.