Blender Cycle rendering full scene now been cut in several path tracing tile


before mid august 2012 all 2.63 version avaliable on included a “full scene cycle rendering mode”
Since this time my rendering scene is cut in small severall tiles, that means I need to wait for the full rendering (tiles) to get the full scene.

I do not have any good GPU but for sure before august the full scene was rendered with noise improving after each frame and it was OK.

Did I miss something on settings or a any upcoming new version ?
thank you for your help