Maximum PC

Hello, I looking to build a home media server for my home. I am currently you my Desktop computer to stream to the rest of the house. I want to build a home server that can house all of the movies, TV shows, music and photos.

I have 2 Apple TV-1 (Convert to run Openelec), An Apple I-pad with XBMC , a old Gen one Xbox convert to run XBMC, purpose build HTPC run XBMC, 2 Laptops, and an additional Desktop. I have a collection on HD and SD video file. I would like a little run for further expansion. I do not see any more than 5 clients drawing from the server at any one time.

I would Like something that is low power for the 24/7 power on requirements. I have the hard drive already. Planning on add more in the future when need. I have 3 x 2Tb and 1x 1Tb for the media. I have an spare 500gb for the operating system, all SATA.

I was looking @ ASUS C60M1-I AMD Fusion APU C-60 for the mother board but I am unsure if it is going to be able to keep up or not. my Budget is not determined yet but would like to not spend more than i have to.

The Component I would need are a Mother board, CPU, Memory, Power supply, and case.
I am open to any operation system for this. any suggestion would be greatly appreciated thank you for your time.

Rut