[sudo-discuss] seeking a low-power computer with 2 or more ethernet ports

i'm looking for a small low-power computer with at least two ethernet ports. gigabit would be preferred although i wouldn't turn down an older one since I have nothing at this point. I want to make a router for my house, to go between the comcast bullshit and my internal network. just a raw motherboard would be fine but with a case is fine too. i should mention that i want something that doesn't take unnecessary power, and ideally i'll be powering it from 12vdc using a little converter like this: https://images10.newegg.com/NeweggImage/ProductImage/ACJ4_1_201706217303591… thank you -jake