Hello there i´ve a question: Where to learn how to use the Openglslang(page)??? i have a Radeon 9800XT(i think it will work, yes?) And if anyone knows the solution for this problem, please post it: I tried to to get started using Cg with opengl and copied the nehe tutorial 47. I have downloaded the cg toolkit from nvidia and installed it. I´ve compiled the whole code and got no errors(i´ve included all libraries and headers). The problem is, the test to see if the required profiles (ie, extensions) are supported always fails. // Get The Latest GL Vertex Profile cgVertexProfile = cgGLGetLatestProfile(CG_GL_VERTEX); // Validate Our Profile Determination Was Successful if (cgVertexProfile == CG_PROFILE_UNKNOWN) { MessageBox(NULL, "Invalid profile type", "Error", MB_OK); return FALSE; // Here is the fault } I have a valid RenderingContext(a grid is drawn). I am trying to solve this problem for months. Nehe´s version does get a valid profile. Why not mine? Please help me.