One thing that formed a large part of the marketing for the Steam Deck was that it would essentially be a hand-held PC. This meant it would be possible to remove the built-in operating system and install something like Windows, instead. With Valve now releasing drivers for Windows 10, gamers can opt for this OS rather than the Linux-based one that comes pre-installed on the device. However, it looks as though there are teething problems with this, as a recent benchmark test shows that games running on the Deck via Microsoft's operating system may suffer frame rate issues.
In the video uploaded to YouTube a few days ago, the Linus Tech Tips channel has put the Steam Deck through a series of tests, in which two devices are compared to each other. One of which has SteamOS as it comes out of the box, while the other has a copy of Windows 10 installed. Playing a number of modern games, the results show that the latter device actually makes game performance worse, with a notable drop in fps during play.
In essence, while the performance of the newly-released Elden Ring doesn't seem to take too much of a hit, the benchmarks show that the likes of Hitman 3 and Doom Eternal show a significant drop when played in Windows 10. In the test, the former went from 34 fps to a piffling and, quite frankly embarrassing, 19 fps, while the latter went from a smooth 60 fps to 47, which is still not bad but is quite a discrepancy, especially given that, in the video, it shows some stuttering from Eternal. By comparison, Elden Ring didn't seem to suffer from the same issues, so is likely better optimized for Steam Deck running Windows.
It's still early days yet, so it's likely that Valve will release some updated drivers, which should hopefully sort any performance issues out. With the Steam Deck coming to more countries later this year, it's in the developer's interest to make sure that games can run as smooth as possible, and that includes for anyone who wishes to install Windows 10 on it.
While there are lots of AAA games now being verified for the Deck, such as The Witcher 3, it's a device that is going to need a lot of tinkering with by Valve as people are praising the device, but noticing a few issues with it. The general result here seems to be that those wishing to install Windows 10 on the Steam Deck should do so with some trepidation, or just stick to the superior SteamOS instead.