Steam Deck runs Portal RTX but with serious compromises

Path tracing usually requires powerful gaming hardware to run, but one enthusiast has made it work on a humble Steam Deck – though there is a catch.

Video game developers are always chasing new technology that can make games look ever more vibrant, realistic, and immersive. The latest tool they have available for this purpose is Path Tracing. Path Tracing is related to Ray Tracing in that both follow light rays through a scene. Though where Ray Tracing tracks multiple rays, Path Tracing only follows the most likely path that light would take, lending more realism.

Path Tracing has been used in titles such as Cyberpunk 2077 and Alan Wake II to impressive effect. Nvidia also created Portal with RTX, a mod that allowed Nvidia to show off the capabilities of its RTX Remix platform. Usually, Path Tracing requires powerful hardware such as a Nvidia GeForce RTX 4080 or RTX 4090 in order to be playable, but a video has shown that with clever tweaking it is possible to make it run on the Steam Deck.

Path traced lighting on a Steam Deck

Though the specs of the Steam Deck are fairly impressive for its size and form factor, it nonetheless doesn’t have the power and capabilities of a GPU like the RTX 4080 or 4090. NightSightProductions on YouTube posted a video demonstrating how they got Portal with RTX working on the Steam Deck.

The video shows that various settings needed to be adjusted, such as turning off secondary bounces for the path-traced lighting, and a downgrade from the four bounces usually used on Ultra settings. The biggest compromise, however, was that the resolution needed to be dropped to 864 x 486 in order to obtain a stable and playable 30 FPS.

It is unlikely that many users would be happy with such a low resolution, but it shows that impressive results are possible with technology such as DLSS and FSR if you take the time to experiment with settings.