still no cheap ARM streaming only steammachine...
As far as I know the streaming part is still a closed source x86 blob. Maybe once the Pyra is released someone (maybe ED, as the boss, although perhaps someone else with enough clout, I dunno) can approach them and ask about it.
The Nvidia Shield TV (code name X1) does all this and runs on an Nvidia Tegra K1 ARM SoC.
It's by far the most attractive SoC out their, with the 256 Core Maxwell GPU and a Octacore Cortex CPU (4x A57, 4x A53).
PLUS, it's only 199$ W/ the controller, the cheapest price point for an SoC of that magnitude.
http://shield.nvidia.com/android-tv
Sorry, but that's exactly what I'm not interested in... a costly, too powerfull ARM console that won't be compatible with a vast majority of steam game but will support a crapload of uninteresting android games... what I'm interested in is something like steam link which does only the streaming I want and for only 50$ (or 100$ with the controller)
Check with their GRID program, you get to stream all of their games for free with purchase.
Steam machines are nice, but for the pricepoint you'd almost be better off looking into a Gaming laptop.
The problem with steam machines, is their just on the razers edge between Small form factor, and performance.
If you could find a HTPC case with support for ITX motherboards and a full length PCI-Express slot, you could basically build a i3-4xxx with any GPU you want.
I ran a G3258 Pentium @ 5.2Ghz (Liquid cooled) along with a R9 290X and a 512GB SSD. If I removed the liquid cooler and opted for a PCI-Express Ribbon cable I could easily fir it in one of those HTPC cases. Deffinatly would not look pretty on the inside, but would be functional.
If streaming is of any interest to you, Just get something like a used GTX 660 or 760 off ebay for cheap (Talking like sub 100$) and just stream it to something like the shield I mentioned above, you could have the whole shabang for under 300$.
Only other real Steam machine option is the Alienware Alpha, which is actually at 500$ a pretty fair price point if you don't want to build your own. But again, at 500$ I could probably build something in the 2x-3x+ range of performance.