Sorry if this question is completely naive but when I connect a harddrive I have, it doesn't even start up. Is there anything I can do here or is this drive trash? I'm just thinking that if whatever powers the drive is damaged, then perhaps the content of the drive is still fine??
If there's ANYthing I can do I'd love to hear from someone.
If you have two identical drives (down to the revision), you can swap out the controller board on the underside of the drives and it may work. I've seen other people do it, but never had the chance to try it myself. Mostly because all of my dead drives are from a decade ago and I only had one. My data wasn't valuable enough to hunt down another controller card.
Depending on the problem and on the model, sometimes there is an easy, no-cost DIY fix. But until you tell us what "this HDD" is, and until you show us a photo of the circuit board, then nobody can even begin to help you.