Which exact PSU do you have? Your motherboard only has PCIe 3.0 so you'll lose about 5% performance on the current highest-end GPUs and the CPU will be a bottleneck (even at 4k) for most games but as long as your PSU has 3x PCIe 8-pin you could even go as high as the 7900 XTX:
Order Asrock Radeon RX 7900 XTX Phantom Gaming OC 24GB GDDR6 PCI-Express Graphics Card now online and benefit from fast delivery.
www.overclockers.co.uk
The AB350 motherboard can take better processors too, so if you wanted to in the future you could drop in something like a Ryzen 5700X3D which would make the build a bit more balanced. If you're only targeting 60fps at 4k though while the 2600 does bottleneck the GPU in a pretty big way, it's still able to maintain 60fps in a lot of games (excl Cyberpunk):
https://www.youtube.com/watch?v=jWVFtX0hAls
It's really depends whether you want to upgrade your CPU in the budget too and have a slightly less 4k future proofed GPU (i.e. 7900XT) or if you want to spend all your budget on one of the most future proofed 4K GPUs and then upgrade the CPU afterwards.
