jts_2003 (7/19/2010)
I also agree with the comment of making the TempDB files as large as possible - the last thing you want is a delay to a transaction because TempDB has to autogrow. But I wouldn't suggest using the whole disk, maybe 80% - that way you've got room to grow in an emergency while you work out what caused all the space to be used up!
There's something funky about this logic. You're not increasing space in an emergency; you're artificially limiting space to begin with, and adding the overhead of an autogrow in an emergency. If you think a query might pass that 80% mark, wouldn't it be better to dedicate 100% of the disk to begin with?