If that's the correct diagnosis, and you're PC is working again, then I'd take really good care of that tech - he sounds like a good one.
This guy is amazing. He's always gotten to the root of the problem and he charges reasonable rates. He ran diagnostics on the hard drive and said it's running fine. My PC had been clicking and then it started clicking and pausing and chugging its way back up before the power would come back full force, but I didn't understand what that might be caused by. It finally gave me a blue screen with a "No boot device found" message. The tech / shop owner was recommended to me by someone who used to work with him elsewhere, at Boeing I think. He said the guy was amazing and he made a believer out of me. He's rescued more than one crashed hard drive for me. I've learned a lot from him over the phone as he's patiently explained this and that to me.