Moving tempdb to a new location:
1) Connect to the SQL server and run this query:
USE master
ALTER DATABASE tempdb MODIFY FILE (NAME = tempdev, FILENAME = '[new path]\tempdb.mdf');GO
ALTER DATABASE tempdb MODIFY FILE (NAME = templog, FILENAME = '[new path]\templog.ldf');GO
2) Stop the SQL service
3) Move tempdb.mdf and templog.ldf to the new location
4) Start the SQL Service