Inherited a free iMac with HD issues

[curtong]

Someone donated a non-working iMac to my theater. It will be a fantastic addition to our sound booth and I had just written a grant for new computers, so it's a serendipitous confluence that someone donated this one. I know nothing about it except there is a post-it note on it that says "bad HD" Primary use will be sound cues, pre-show "previews" via projector, and light sound editing for voice-overs and foley.

Assuming that is the correct diagnosis, tell me what I'm in for. I'm modestly capable of doing surgery on PCs. I've heard conflicting answers regarding replacing the HD. Some say that I absolutely have to buy one from Apple and it's huge money. Others say that a HD is a HD and I can just buy a Seagate. Others say that I can use any drive as long as I have an adapter.

Once I replace it (if I can do it without spending a fortune) how do I install the OS? Any specific OS I should use or avoid?

Can you tell I've never been a Mac user?

 

[Darren]

Might be good to know the model to start with.

Been a couple years since I worked on them but getting into them can be a nightmare. Older ones you could just suction cup off the front glass but newer ones are glued down I think. Could be wrong though. If I recall we just used normal hard drives in those, but I honestly don't remember for sure.

Installation is stupid easy. Just need a bootable flash drive with the .dmg on it of the latest OS X version. Also can connect to internet and just pull it. I'd just get the latest it supports.

How to install macOS or OS X on a new hard drive for your Mac

You may need to install a fresh version of macOS or OS X if you get a new hard drive in your Mac. We've explained exactly how to do it!

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