Compute device for rendering

Hi,I am trying to find the option to change the render device from cpu to gpu.
Wiki said i had to activate it through system in order to get it to the render panel.
Under preferences and system,I found the Compute device option but when I click it I get only the CPU as an option.Any ideas why?

Thanks in advance!

What is your graphics card ? Does it meet the minimum requirements in the blender manual for gpu rendering (link to manual in the blender help menu). If it is not compatible with cycles gpu rendering it won’t show up.

Ge Force 9600 GT
I found a sentence in wiki that says “Computing capability 1.x cards are no longer supported, but you may still be able to compile experimental builds with a limited feature set (see below).” and in the list,my graphic card has 1.0 Compute capabilty,so is this the reason it does not appear?

Yes. Even if it would work you’d most likely get faster rendering with your cpu.

Ok , many thanks.I ll edit it “solved”.