At minimum something like this
. Even absent the resolution and refresh rate, 3200C16 is dirt cheap in a build where a 2080 Ti is on the table, and is worth every penny. Past 3200C16 it gets less clear.
With a 1440p144 monitor and a 2080 Ti, you could easily be very CPU-bound depending on the games you're playing and settings you're using. What's your actual framerate goal? If it's true 144 (for ULMB for instance), RAM at more like 3600 could be good, and I would highly recommend a K-variant CPU (probably 9700K) for the stock clock bump (larger power budget) even if you don't plan on overclocking. If seeing 100 fps often would be alright, a 2080 Ti for 1440p is probably very overkill, but the CPU-side requirements (including RAM) are a lot more relaxed.