Hi, under Windows 7 Service Pack 1 with Platform Update you cannot use any D3D_FEATURE_LEVEL_11_1 and DXGI 1.2/WDDM 1.2 features.
This mean you can only use a limited set of Direct3D 11.1 under Windows 7 Service Pack 1 with Platform Update.
You can read more about here: Platform Update for Windows 7 (Windows)
PS: by the way you GFX Card (AMD Radeon 5950 series) does not support D3D_FEATURE_LEVEL_11_1.
Yes I'm aware of that.
I don't want hw specific features like new shader instructions or binding uav to any shaders,.. what I need is , some d3d11.1 api features that are likely currently exist in the driver implementations.
For example I need MapNoOverwriteOnDynamicConstantBuffer for my application, which the OpenGL equivalent (glMapBufferRange, glBindBufferRange) existed since v3.0. And when I call for example VSSetConstantBuffers1, Debug layer complains that "This current driver does not support constant buffer offsets".
And this is what says In the d3d documentation for VSSetConstantBuffers1: "This feature is always available on new drivers for feature level 10 and higher."
I also didn't manage to get them working, even on D3D 11.1 hardware. However, it was the same for NVIDIA. For using the D3D 11.1 API only features, I had to run Windows 8, on Windows 7, I would get the interface, but everything would be set to unsupported on Windows 7. If you look at the D3D11 Options documentation, it also explains that a few features are only available together, and given that the 5950 only supports D3D11.0, that could be part of the problem as well. Not sure if there is any driver shipping with those extensions. Did you try with WARP or the reference rasterizer and see if that works?