Why Opencv GPU code is slower than CPU?

Question

I\'m using opencv242 + VS2010 by a notebook.
I tried to do some simple test of the GPU block in OpenCV, but it showed the GPU is 100 times slower than CPU codes. In this

Answer 1

What GPU do you have?

Check compute compability, maybe it's the reason.

https://developer.nvidia.com/cuda-gpus

This means that for devices with CC 1.3 and 2.0 binary images are ready to run. For all newer platforms, the PTX code for 1.3 is JIT’ed to a binary image. For devices with CC 1.1 and 1.2, the PTX for 1.1 is JIT’ed. For devices with CC 1.0, no code is available and the functions throw Exception. For platforms where JIT compilation is performed first, the run is slow.

http://docs.opencv.org/modules/gpu/doc/introduction.html