GPU is slower than CPU

Hi.
Maybe your case is similar to mine, but with hardware these days (sorry to put google cache link, but I can not find the old thread in the new forum):
https://webcache.googleusercontent.com/search?q=cache:kmG4hD3oeO4J:https://blenderartists.org/forum/showthread.php%3F375718-Cycles-GPU-CUDA-slow-with-some-materials%26styleid%3D14

But to clear up doubts, you perform the following benchmarks with official Blender 2.79 (2.79b) and compare results with others. You must download the corresponding files of each thread: