DirectX 12 is supported by all Ampere, Turing, Pascal, Maxwell, Kepler and *Fermi GPUs.
Note: Feature Level support can vary between GPU series, see below:
You can check which DirectX Feature Level your graphics card supports using the DirectX Diagnostic Tool:
1 - Open the Run command by pressing Windows + R or searching for Run
2 - Type dxdiag in the dialog box and click OK or press Enter
3 - Select the Display tab, and if you have multiple monitors, choose the one connected to your dedicated graphics card
4 - Locate Feature Levels in the Drivers section and supported Feature Levels will appear there.
For more information on Feature Levels please check here.
*Please note: Effective April 2018, Game Ready Driver upgrades, including performance enhancements, new features, and bug fixes, will be available only on Kepler, Maxwell, Pascal Turing and Ampere series GPUs.
https://nvidia.custhelp.com/app/answers/detail/a_id/4654