WhatPSU.com を使用すると、CPU モデルと GPU モデルを入力するだけで、PC に必要な電源を簡単に見つけることができます。

I need to know what PSU do I need

This is an automatic calculator. Choose your PC's CPU and GPU (or only one of them), and click the "calculate" button. You'll get as a result the minimum PSU you need for this rig and some recommended PSUs

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