Where does the Windows Bluetooth stack come into play?

Windows 7's Bluetooth stack does not support Bluetooth 4.0 Smart. I need to use a 4.0 Smart device.

If I install a network card with Bluetooth 4.0 support, does that mean that it will install its own Bluetooth stack...?

If the above is true, do most Intel cards install their own Bluetooth stack? How about Atheros?