Your sig says you're running Windows 10. Which version? Apply the Anniversary Update yet?
My understanding is Fast Boot delays unnecessary USB device loading until the OS load. Now, the behavior I see with it enabled is that, after post, all the lights on my USB devices go dark (even the keyboard and mouse), the Windows 10 spinning dots do 3 full revolutions, then the usb lights come back on and the login screen appears. That period comprises the bulk of my boot time.
I'm pretty sure I tried disabling Fast Boot so that all USB devices would be loaded by the time the OS started, but it seemed to make no difference.
So... do you get the extended spinning dots with usb device lights off with either setting?