https://www.pcgamer.com/rainbow-six-siege-benchmarks/

Rainbow Six Siege launched at the end of 2015, and it's experiencing a minor renaissance today. If you're hoping to become more competitive for the latest season, hitting 144fps on a high refresh rate monitor definitely helps. But what sort of hardware does that require? To answer that question, I’ve put together a suite of test results on all the latest graphics cards, along with several previous generation parts, and three gaming notebooks. I've also collected benchmarks from seven of the latest CPUs, though Rainbow Six Siege ends up being relatively tame when it comes to CPU requirements (at least if you're not livestreaming).

Many competitive players drop to lower quality settings to boost framerates, but it’s important to point out that Siege uses render scaling combined with temporal AA by default. The render scaling is normally set to 50 percent, so unless you change the setting, 1920x1080 renders at 1360x764 and then scales that up to 1080p. This of course introduces some blurriness and other artifacts, and if you want optimal visibility I recommend setting this to 100 percent scaling (or disable temporal AA).