So I've recently rebuilt my old Hp Microserver and its dog slow. It's about 6 years old and has 4 2tb drives in it. Used to stream films from that to my boxee box. I've recently installed plex on my Xbox one and in future at Apple TV. The Microserver isn't powerful enough to transcode anymore...so I can either get the new gen Hp Microserver or build a NAS box that can transcode and host my 4 2tb drives and be small. Main worry with this is cost and if I went self built I'd want it to be able to process 4K. Any recommendations?