http://blogs.msdn.com/bencon/archive/2007/12/17/a-debug-device-really-does-need-the-debug-layer.aspxD3D10_CREATE_DEVICE_DEBUG is a really handy thing to use: http://msdn2.microsoft.com/en-us/library/bb204909.aspx Watch your debug output with this turned on and you will get a lot of helpful stuff. Try rendering without a viewport, for example. One thingen-USCommunityServer 2.1 SP1 (Build: 61025.2)