From Identity Finder technical support in answer to the question of SQL Server configuration for a 3000 IDF endpoint system:
The database is primarily bound by disk speed and secondarily bound by number of CPUs and RAM. For 3000 endpoints you'll need to make sure you are using at least SQL Server standard edition as SQL Express has too many limitations that will affect your performance. You'll want at least 2 cores (or CPUs), speed of the CPU doesn't necessarily matter, just as long as it is fairly recent (I would say, 2.0Ghz or higher).
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