Red Dead Redemption 2 Steam Version, December 9th 2019. Using the 440.97 Nvidia drivers (not the newest but optimized for rd2).
PC: 2600X, 32GB 2400mhz, RTX2080FE. The 2080 has less vram but is in performance similar to a 1080ti. Target is 99% 60fps with headroom. I set all settings to the absolute maximum this card can handle in most situations. You'll see in the city a use of ~80% but in the forest around 90-95%, leaving only 5% left to prevent frame dips. I have not tested all of the game yet but this gives a good idea of the performance for your Ultrawide I think.
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