Here ya go...i wish people would really research further and have a definite answer before saying something that's false.
http://blogs.nvidia.com/blog/2014/09/19/maxwell-and-dx12-delivered/
"DX12 contains a number of improvements that can be used to improve the API’s CPU efficiency; we’ve announced that all Fermi, Kepler, and Maxwell GPUs will fully support the DX12 API - See more at: http://blogs.nvidia.com/blog/2014/09/19/maxwell-and-dx12-delivered/#sthash.Sz2UooZE.dpuf"