What CPU Should I Upgrade to for My New GPU?

Keep in mind, most AM5 CPUs will likely bottleneck your GPU. You might need to move to an AM5 platform if you want to avoid that.

Are you thinking of sticking with the Ryzen 7? It could be worthwhile to look into getting a newer generation along with a new motherboard.

It really boils down to how your games are running. If you're getting bad dips in performance or stuttering, consider lowering some settings. If you're not satisfied with that, then look for a Ryzen 7 5700X3D chip. They can be pricey, but if you find a good deal on a second-hand 5800X3D, that’s an excellent choice for your setup, just don’t forget to update your BIOS first.

If you're gaming at 1440p, your current CPU isn't too terrible in most games. Some CPU-intensive titles might cause frame drops, but on average, you shouldn't see a massive difference. I use an i5 12400F with a 5070 Ti, and I'm only about 10-20% faster in most cases. For example, in "The Last of Us Part II Remastered," I noticed about a 20 FPS dip. You’ll probably fare similarly, so it’s manageable depending on what you play.

I think you meant the 3700X, but you're still in a good spot if your monitor supports 144Hz. Personally, I recommend upgrading to a 5700X3D to really maximize what your system can do; if that's not available, a regular 5700X is a solid choice too.