What Valve hasn't said, but we can surmise from previously released information, is that you're going to need a very, very fast desktop to run SteamOS successfully. The Steam Machines are believed to use Intel Core processors. The only CPU we know for certain that will fully support SteamOS is Intel's quad-core Core i7-4770.
SteamOS also appears to need a lot of memory. The Steam Machines are supposed to come with 16GBs of RAM.
You'll also need a mid-to-high-end Nvidia graphics card. We know the top of the line Steam Machines will use Nvidia's GeForce GTX Titan with its thousand-dollar price tag. Fortunately, you'll also be able to use the more affordable Nvidia GeForce GTX 660, GTX 760 or GTX 780 cards.
Valve's Steam games originally ran on Ubuntu but Valve has gone its own way with its Linux distribution. So, in addition to having some seriously well-muscled hardware, you'd be wise to listen to Coomer when he said that SteamOS in its early days will be for Linux hackers, rather than someone who just wants to play a game.
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