Turbo Boost is automatic if enabled by the BIOS and the OS.
You BIOS settings for C states need to be enabled
and the 2008 power preformance settings need to be set to balanced, not preformance. (preformance will lock the CPU's at the rated max speed and prevent the unit from going into turbo boost mode.
Some software that monitors turbo boost may require a driver, but turbo boost does not.
You can see this link for other FAQ on Turbo boost.