New analysis shows that games perform far worse on Valve's SteamOS than they do on Windows PCs.
The Steam Machines have only just launched, after years of chat about them from Valve, with the promise that they'd offer a new kind of gaming experience powered by a unique gaming-focused UI.
However, new analysis from website Ars Technica show that the Steam Machines and the new SteamOS might not be all they've been talked up to be.
The Linux-based Steam Machines can't stand up to the Windows PC running on exactly the same hardware.
According to the results, Windows 10 gaming scored better on every single metric, although often the margins weren't that large.
However, results for titles such as Middle-Earth: Shadow of Mordor and Metro: Last Light had differences that were basically night and day.
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Apparently, even games running Valve's own Source Engine still performed better on Windows PC than on the Steam Machines.
Most AAA titles still aren't available on SteamOS, so further comparisons can't be drawn at this stage.
The Steam Machines still seem a very nice product, due to their high costs, limited games library and now, reduced performance.