You can do it by running alter database statement. You can look at the script .that I’ve added as an example. Unfortunately you'll have to restart the service. Without restarting the service, tempdb will continue to work from its current position.

use master

go

--Change the location of the data file. .

Alter database tempdb modify file (name = tempdev, filename = 'D:\MyTempDBDir\tempdb.mdf')

Go

--Change the location of the log file.

Alter database tempdb modify file (name = templog, filename = 'E:\TempDBLogDir\templog.ldf')

go

Don't forget to use the real path and not the path in this example.

Adi