Ugh. What a mess!
I generally eyeball the power requirements for the individual parts and then add a few hundred watts to provide extra headroom for future upgrades and power hungry tasks that I may perform. For instance, 750W was recommended by the linked tool in the Reddit post but I went with a 1000W power supply. Definitely overkill for most tasks but it’s generally better to have it and not need it than need it and not have it 🙂
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