I had the same issue with a 4070 super. Also I noticed that the framerate was low and dlss did not have much effect. I got somewhere around 30 fps often going to 20.
I have now changed to nvidea surround and it makes all the difference. Fps are at 80 with most settings on ultra. Textures are stable also the weird artifacts I had at the edge of my middle monitor are gone.
Oh and if you are going to use surround check out DisplayMagician because switching display modes in the nvidea control pannel is a pain.