No surround sound, only two channel.
I do have some cd's and a disc drive but if nothing else I can just import them to my current pc move them to a external hard drive then move them to the new computer. I rarely get new CD's
I just looked my current PC has 450 gigs and says 229 are free... I move stuff I rarely use to my external hard drive so storage should not be a problem
will the mother board have the outputs I want? If I don't use a sound card or a disc drive where will my audio and video outs come from?
If you use that less storage, a 256gb SSD should be okay and continue using external storage. Even then, 500gb SSDs are starting to hit ~$300 which is relatively cheap.
Does your DAC not have USB input?
If you build around a passive ITX case, this motherboard would be a great option for you: http://www.newegg.com/Product/Product.aspx?Item=N82E16813128615
Has dual HDMI out and DVI plus built-in wifi.