The official Steam Machine return is imminent, but its specs leave enthusiasts wanting more. I've taken matters into my own hands by gutting a rare 2013 Valve prototype and stuffing it with a Ryzen 7 9800X3D and a Radeon RX 9070 XT. The result is a 4K living room beast that runs SteamOS natively, though conquering the heat and console-like features required some serious engineering.