Chris Shaw tells us to optimize TempDB:
By default when you install SQL Server the TempDB database is not optimized. For SQL Servers that use the TempDB even moderately, I recommend optimizing it for the best performance. The TempDB is the storage area that SQL Server uses to store data for a short periods of time, information that can be found in the TempDB include temporary tables, and data that is being sorted for query results. The data in the TempDB is so temporary that each time the SQL Server service restarts, the TempDB is recreated.
Good advice within.