Okay I'm cheating a bit as I have most of the components already, I'm going to be using my HTPC's old case and PSU (Silverstone Milo ML05 and a 80+ 300W FSP PSU [can't remember the model number]) and I also already have the 2TB hard drive in an external USB enclosure like a cave man and a spare 32GB SSD for the OS and 6GB of DDR3 laptop RAM.
So basically all I need is a motherboard, CPU and 2 fairly quiet 80mm fans for the case.
The goal here is to store all our media (Music, Movie and Images) and be able to stream it and all my work stuff (I work in basic IT so mainly diagnostic tools, OS images, portable AVs and AMs etc etc.) but to do so with as little power consumption as possible without it chugging, There's only 3 main machines in the house, mine and my wife's desktops running on Windows and my atom based netbook running Linux Mint which I mainly use for work.
So far I think this might be the best way to go:
and 2 of these: http://www.computeruniverse.net/en/products/90158715/sharkoon-system-fan-s-80x80x25mm.asp
My main concern is even tho that CPU is hella light on the power I'm just concerned if it can cut the mustard in a FreeNAS machine or weather it's overkill in my situation and that I should just save about €30 and get the dual core version instead, or is there even a third option I am missing here?
I've built plenty of NAS based servers in the past but only using Windows Server for heavy use and nothing as low quay as this so you can see where I might need some help on this.