A common use for an old PC is as a NAS. If the old PC is running a Windows or Linux you just add your drives and share them like any file server over the past few decades. It would plug into your router.
I am thinking of using an old pc for data storage was thinking of getting a sata controller to attach my hdd's do any of them have an option for output i would like to plug it into my current pc or is there another wired option

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