So there is a bios error, that prevents CPU to shift to single core max speed at x99-TF Huanan board.
You must have disabled the CPU power management in BIOS that results in static base clock on all cores, which is 2000MHz for your CPU.
Or the turbo boost is disabled in bios.
There are some combinations of the powermanagement settings that can cause this.
I suggest resetting the bios to defaults.