C# for Game Programming

Question

I'm about to start programming a 3D game but i don't know which language to choose. i've read that C# performs slower than C++, but C# is far easier to code, especially for threading and object oriented work. What would the performance difference be between C++ and C++ for .net? However, the crucial point for the choice is obviously performance. How would you rate the following languages performance-wise when it comes to 3D game prgoramming with DirectX or OpenGL? C# :: C++ .net :: C++ :: Java cheers