I see. But what if in a future I buy a graphics card such as the ATI RAEDON HD 6870?
A quality 500w psu like TheBigTroll listed will be ok for a 6870. http://www.amd.com/us/products/desktop/graphics/amd-radeon-hd-6000/hd-6870/pages/amd-radeon-hd-6870-overview.aspx#3
Or, a GTX670, for that matter.
But, the reason you buy a llano is because of the superior integrated graphics. The cpu is not as good as intel if you will use a discrete graphics card. Perhaps you should reconsider your build strategy.
What is your budget, and what is the primary use for this PC?