I assumed it was an easy fix any maybe the operator didn't know how to restore. It is a late 2013 model 27 inch, I scored for $850. Dead HD and all, I still think its a great deal, what do y'all think? Anyways, system utility does not find the HD, so I plugged in an external, and I was actually surprised this was an option for me, so I installed it! It's a spare external that'll be temporary, my question(s). Would an external USB 3.0 be just as good or very minimal difference in terms of operation? What is an estimate for a 1 tb replacement? (my nearest store is pretty far and they cannot give quote over the phone) My Craigslist has an "Apple Certified Tech," where I can supply my own HD - Do I need to worry about the fan speed issues (different model/brand HD replacement). Labor is $75 I'm also considering a DIY, but same question as above, do I need to worry about the fan speed problems?