3DMark 11 is designed for testing DirectX 11 hardware running on Windows 7 and Windows Vista the benchmark includes six all new benchmark tests that make extensive use of all the new features in DirectX 11 including tessellation, compute shaders and multi-threading.
After running the tests 3DMark gives your system a score with larger numbers indicating better performance.
Trusted by gamers worldwide to give accurate and unbiased results, 3DMark 11 is the best way to test DirectX 11 under game-like loads.
If you want to learn more about this benchmark, or to buy it yourself, head over to this page.
A score of 871 at entry preset is not a wonderful result from the CX640, but this is a tough Direct X 11 test and a struggle for the modest graphics hardware.