Patch Tool in Photoshop CS (Windows)

Just installed (and re-installed!) CS. I notice that the Patch Tool doesn't behave the way it used to in 7.0. That is, when I drag the selection to the source (or destination) the selection doesn't move only a black arrow. In 7.0 you could see the patch you were copying from or to.

Any suggestions????

er I now see a preview in the desitination patch in CS, no black arrow for me sorry.

I haven't got CS, but I remember reading something about having a choice here between "source" or "destination" method for patch.

Rob

Update: Appears to have been a memory problem. I upped the memory for use by Photoshop in preferences. I now see the preview and the selection as I move it.