I recently bought a computer and graphics card specifically to run Zwift. As there are no lists of graphics cards which run Zwift in Ultra (zwiftalizer seems to have pulled its benchmarks) I bought an AMD Radeon RX 570, 8 GB. That card scores comparably to an Nvidia GTX 1060 on https://gpu.userbenchmark.com/ and http://www.ozone3d.net/gpudb/scores-geeks3d-furmark.php. Based on those tests, I figured the card should be able to handle Zwift in Ultra with no problem.
However, Zwift only runs in High graphics profile, not Ultra. (In High profile at 1440p, I get 90+ FPS.)
I contacted Zwift support and was told, “the game auto directs what graphics card you are using, and applies the most optimal graphics profile. While your GPU may be able to display our Ultra graphics, it may lead to a decreased frame rate or other graphical issues. Because of this, our development team currently has the card in the High graphics category.” and " I would encourage you to share your ideas on our feature request forum or vote up other request to have the profile added."
So, I’d like to see an Ultra graphics profile for this card.