2015-07-19, 22:08
If you go the linux x86 way, and want 4K quality using H264, a Haswell 2955U (chromebox or similar) should be enough. Another alternative which supports 4K HEVC hardware decoding is the new Intel Braswell (no HEVC linux support yet though but it's still early days). And a motherboard like the N3150-ITX should have all the audio outputs you need.