The simplest answer is, the cheapest one that can output your monitor's native display resolution at its maximum refresh rate without using within 20% of your PSU's total watts. IOW, you don't need an RTX 3080 if you have a 1080p monitor.
What graphics card do you recommend for the best gaming experience? For more questions regarding this contest, please visit the Information Page here.
DS 07/24: What graphics card do you recommend for the best gaming experience?