I have a Phenom II x3 720 processor in my desktop which I cool with a CM Hyper 212+. I am in process of researching for a HTPC and am planning on building it with an APU. I was wondering if (a) it is possible to use the old stock cooler from the Phenom II for the APU (are the FM1 and AM3 brackets the same), and (b) if there is any reason not to, even if it is possible.
The 720 BE is rated 95W while the top end Llano's are rated at 100W - 5W shouldn't make much difference so the 720 cooler should be fine. If you are using a lower TDP chip then the cooler will obviously perform much better. Make sure it fits in whatever case you are buying though.