According to Steam Hardware Survey of March 2016, 70% Systems has DX12 GPU

The Steam Hardware & Software Survey: March 2016 bring some interesting numbers, according to March survey; the number of systems to have DX12 GPU with Windows 10 is 34.56%, and DX12 GPU with older Windows has 35.59%, which means more than 70.15% users are ready for DirectX 12.

Steam Hardware Survey of March 2016

Other interesting things are 56.35% systems have an NVIDIA GPUs, and 25.5% has AMD GPUs. For CPU, Intel holding 76.67% and AMD at 23.33%.