If you already have a GPU that's not keeping up, then I would suggest the best price to performance card you can find within the spec range you are shopping in. Me personally I would go with more VRAM for those more graphically demanding games if you want to run native 1440p and whatnot.
Thank god you did not say it's from some website. That would be suspiciously cheap at this point in time. Hey! That's an awesome friend, enjoy the sweet deal.
Is this system not doing what you need?
You have a really, really, good system. I would focus on other things like that monitor you want to get, and other peripherals to make life and multitasking easier.
I can't read your time spy score.
How many chunks are trying to render?
Give some more examples with temps for both cpu and gpu along with the amountof usage.
Did you use DDU to uninstall the older drivers, then install new drivers from Nvidia?
If the VRMs are getting too hot, make sure you have good air flow in the case.
It's the year 2024, not 2016. Get 32GB of RAM.
I don't know the prices in your part of the world, but if the budget allows, go for the 10 core i5 13400f.