Back in the days when 200 MB was a big drive for a personal computer, IBM was working on a 1 GB drive. I worked at a place that was doing firmware for a company

Back in the days when 200 MB was a big drive for a personal computer, IBM was working on a 1 GB drive. I worked at a place that was doing firmware for a company that was going to use those 1 GB drives in their product, and that company had access to some of the earliest test units. We were writing the firmware for that product, so IBM allowed them to loan us a couple of the drives. I once put one of the drives into my test system, and plugged in the power connector. It used a standard Molex connector [1]. The way the drive was mounted I couldn't actually see the plug or socket. It's a keyed connector so that should not be a problem. Yet somehow I managed to plug it in upside down which fried the drive. Afterwards I did some tests and found that the plastic on the connector on the drive was very soft. If you tried to plug in the wrong way the parts that were supposed to get in the way due to the keying would just deform out of the weight. It took more force to insert it the wrong way, but not more than was often needed when you happened across a plug and socket combination that were a tight fit so that didn't tip you off. I reported that to the person who had loaned us the drive and he told me he'd fried two of them that way. He said that when he told IBM about that his contact there said that they were losing something like 10% of the drives during testing right after manufacturing due to their technicians getting it backward, and the parts list had already been revised to switch to a connector hard enough for the keying to actually work. [1] https://en.wikipedia.org/wiki/Molex_connector https://en.wikipedia.org/wiki/Molex_connector