Sell the RTX and get an Arc 770LE. With twice the Ram and twice the bus width, it’s your video card, not the CPU , that’s the bottleneck.
Real-life stats: Installed 2 Arc 770LEs, on last year’s i5-12400, and CPU utilization dropped off to 16% while flying in an 8192 x 2160 window stretched across two 50" screens. And it will only get better when they add XeSS support.
I fully expect that CPU to be able to support 16k x 2k when my two 65" side screens finally arrive, because the choke point is no longer the CPU (which before I upgraded the video cards, was often maxing out), and at that resolution, supplying the current 4 screens, I’m barely using half the GPU capacity, so a 3rd one on each is not unreasonable.