Yes Daveeb, I read about that, and knew about your problem, unfortunately.
In fact, I can't understand why that problem happened with you more than others. As you well know, my knowledge is limitted.
But I just wanted to add that point in case someone thinks one day of it.
Another point is important to mention here, in case you or someone else thinks to use an external HDD.
If we use an external case (box) of a HDD in which we ourselves put the drive in, The jumper of the hard drive of that external hard drive must be set on the position "MASTER", not another.
I don't think this was the cause of your problem. For, if you set it on another position, it simply doesn't work, but it doesn't cause problems to the PC like it happened with you.
Good chance to all...