Depends on whether or not you have a lot of room on C: for the TempDB to grow as needed. If you only have a couple of GBs, then yes, it is well worth it. TempDB can consume a LOT of space when doing heavy queries or transactions.
We usually don't stick our system DBs on the C: drive because we partition C: so small specifically only for OS files and then stick everything else on a SAN. We also now keep all System data & log files on their own drive, and have a separate drive for UserDB data files and a separate drive for UserDB log files. It's quite efficient. @=)
Catadmin - MCDBA, MCSA
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