Cycles: Problem with shadows of objects with alfa texture

I am sorry if that was already answered before, but I could not find a solution, because I don`t quite understand what exactly I am doing wrong. So, when I try to create a plate with a texture with alpha transparency, I meet some mistake with shadows. When I use the CPU to render a scene, shadow in the background it looks fine, but when I switch to the GPU, transparency still there, but the shadow looks like the entire plate begins to cast a shadow. I have attached a screenshot of what it looks like(transparency is not full just to show you where the plate with alfa texture is), as well as screenshot of a node for a texture(although it simple). What am I doing wrong, and is there a solution, leaving the possibility of rendering using the GPU?
(sorry for bad english)

I’m pretty sure that AMD cards can’t do shadowing on transparent objects so if you’re using one that’s why.

They cannot, as indicated in the blender manual

Yep, I am using AMD. Well, this is sad. Anyway, thanks for helping, at least I know what the problem now.