Graphics card problems

When I play, there are horizontal shifts in the image, small shifts, but noticeable. And the FPS sags in the game very much. For example, the Witcher 2 played, as soon as he came out, calmly 60 fps, this year he decided to launch the first witcher with a total of 20 fps and that's it, went into the second witcher the same thing. Nvidia geforce gtx 460 graphics card