Tips:

2060 Super:
Works natively up to 768x1024, maybe even 1024x1024. "Hires. fix" works with images up to 512x768 but not 768x1024 unfortunately.
Usually: generate images in 512x512. When one image is good, tick "Hires. fix" and the latest seed (used in the previous picture) and re-generate.
If result is not good, you may try to regenerate natively in 1024x1024. You can also retry the "Hires. fix" but decreasing the Denoising strength. This will make the resulting image closer to the 512x512 one, although this may create some artifacts, but not always.