Forza Horizon 5 does feature a built-in benchmark and initially I was looking at using this for my testing today. However, while the benchmark delivers performance that is broadly representative of what you’ll see in game while using an Nvidia GPU, I found AMD GPUs performed much worse using the benchmark compared to what I saw when actually playing the game.
Take a look at the above chart for instance, for the RTX 3080, the delta in performance between the built-in benchmark and actually gameplay is pretty close, especially at 1440p and 4K. Taking 1440p as an example, the RTX 3080 performs just 10% worse in the built-in benchmark compared to my own test sequence. The RX 6900 XT however, performs 31% worse in the benchmark vs actual gameplay, making it a fair bit slower than the RTX 3080 – which just doesn’t match up with the actual gameplay experience.