Can anyone help me?

Hey everyone,
Im having a problem getting cycles to use my GPU rather than my CPU.
iv downloaded a 2.6 version of blender with cycles, cycles works fine but there is no way to switch between GPU and CPU. I know where it should be but there is only an CPU option.
could it have to do with my graphics card? (radeon 5870)
could anyone direct me to a different version?

At the moment Cycles runs only with Nvidia cards. The problem is something in the AMD drivers. AMD said that they are going to fix it some months from now.

that’s unfortunate but thanks for the help with that.