With the first wave of Steam Machines now out the door, the good folks at Ars Technica decided to take a closer look at the performance of SteamOS, the Linux-based operating system on which they run. The site conducted a series of tests on a dual-boot Windows/SteamOS PC using the Geekbench 3 benchmark, because it comes in both Windows and Linux versions, as well as a handful of games.

Windows 10 came out on top across the board on the benchmark scores, but the results were close enough that most folks probably aren't going to lose much sleep over it. The picture changed rather dramatically when it came to actual games, however.

The site opted to use Middle-earth: Shadow of Mordor and Metro: Last Light Redux for its testing, because they're graphically demanding, have built-in benchmarks, and unlike a lot of newer releases, have both been ported to SteamOS. In both cases, Windows 10 outperformed SteamOS by a considerable margin: Shadow of Mordor at Ultra settings, for instance, ran at a playable 34.5 average FPS under Windows 10, but managed only 14.6 FPS on SteamOS.

Similar results came out of Valve's own Source-powered games: Portal, Team Fortress 2, Left 4 Dead 2, and Dota 2, at 2560x1600 resolution and "maxed out settings," ran significantly better under Windows 10 than Steam OS. This is even more telling than the other results, since, as Ars Technica noted, Valve is the one studio that should be able to wring the maximum performance out of this operating system.

It's obviously not the final word on SteamOS, which will presumably (or at least hopefully) continue to improve and be supported by increasing numbers of developers. But right now, it's sure not going to help Valve put machines in living room.