iFixit found interesting details under the hood of the Steam Machine after a complete disassembly. Perhaps the most interesting find is the relatively modest build, which happens to have a 1 TB hard drive.
Bear in mind that many of these details are of limited use. Valve has already released some details on the specs for these machines, and have released SteamOS itself. Also, there is the eventual release of commercially available Steam Machines from manufacturers themselves. What we can learn here is what Valve decided would be the minimum their 300 beta testers would need to test out, use, and possibly hold onto, their Steam Machines.
Before getting to the console itself, iFixit opened up the bundled touchpad controller 1st, finding, among others, an NXP LPC11U37F ARM Cortex microcontroller. Note that this is a wired controller to boot.
These are the parts iFixit took out of the Steam Machine, in order of disassembly: a 1 TB Seagate SSHD (Solid State Hybrid Drive). Next up was a ZOTAC GeForce GTX780 3 GB GDDR5 graphics card, a SilverStone RC2 PCI Express x16 riser card, an ASRock 787E-ITX MiniITX motherboard, two Crucial Ballistix Sport 8 GB DDR3 RAM cards, a Zalman CNPS 2X Mini-ITX CPU cooler (heatsink fan), Intel Core i5-4570 3.2 GHz, an NXP LCP11U24F ARM Cortex microcontroller, apparently just for the giant power button and LEDs, and lastly, a Silverstone SST-ST45SF-G 450W SFX12V SLI PFC Power Supply.
Having been designed to be easily opened and taken apart, and being made of mostly off-the-shelf parts, the Steam Machine is very easy to repair, as well as upgrade the hard drive and video card. The biggest issue may be removing the RAM, requiring you to take out the motherboard cowling to do so. Personally, the biggest surprise were the two ARM Cortex processors on the controller and the power button.
Bear in mind, again, these are the components Valve thinks were best to test out their SteamOS, and possibly their best projections on what they can give out to beta testers to use for a long time. It’s no slouch, but the build does not particularly strike me as too high end. Would you build a Steam Machine like this yourself?