windows 7 x64 - DirectX won't let me use D3D_DRIVER_TYPE_HARDWARE despite having a DirectX11 capable Graphics adapter -

windows 7 x64 - DirectX won't let me use D3D_DRIVER_TYPE_HARDWARE despite having a DirectX11 capable Graphics adapter -

i'd utilize sharpdx rendering engine of wpf project (windows 7, 64 bit, directx10 / 11) i'm running problems getting samples work. can utilize directx 9 samples though. problem not straight related sharpdx since i'm seing similar problems slimdx , other directx samples.

the directx driver types work when using direct3d 10 / 11 d3d_driver_type_reference , d3d_driver_type_warp. d3d_driver_type_hardware not seem working. not impact sharpdx, c++ samples allow me take between rference , warp drivers.

my understanding drivertypes simply software rasterizers. implies directx installation not working properly. don't see errors, latest drivers installed , scheme reporting directx 11 drivers , graphics adapter supports directx 11.

dxdiag not reporting errors dxdiag confirms directx 11 drivers installed i'm using gt 460, should back upwards directx 11 system windows 7 (64bit) / vs2013

sharpdx able create devices vertexshader created or swapchain set dxgi_not_supported or e_nointerface errors.

i swapped graphics cards radeon hd 5450 nvidia geforce gt 460 no avail. sharpdx samples run fine on computer windows 7 , intel on board graphics. can give thought going on here? why can utilize warp , reference drivers despite having directx11 capable graphics adapter?

any help appreciated. references found online such issue running ide within vm did not have proper 3d drivers.

windows-7-x64 sharpdx direct3d11 direct3d10