You can run Forza Horizon 6 on an unsupported AMD RX 400/500 series GPU on SteamOS

This post serves as a personal bookmark and a mirror of this fantastic guide by Ok-Pace-1900 on /r/linux_gaming to ensure that this information does not get lost. I learned the hard way that the GPU I have in a DIY Steam Machine PC, the AMD RX 480, is strictly unsupported by Forza Horizon 6. Forza Horizon 6 will not work for AMD users with GPUs based on the Polaris or Vega architectures and older (for example Radeon 400 and 500 series players). These architectures are below our minimum supported specification. I knew that asking for a refund on Steam would be the easy way out. Deciding against it, I did a quick search for the FH201 error code and stumbled on the Reddit post mentioned above. My CPU is good enough for Forza Horizon 6 (Intel i5-10500), so the additional launch options command that worked for me is the following: VKD3D_FEATURE_LEVEL=12_1 VKD3D_CONFIG=descriptor_heap,no_upload_h_vram RADV_EXPERIMENTAL=heap,sync2 radv_wait_for_vm_map_updates=true %command% It's Forza time!…