Sounds like they burned up the CPUs with an inadequate cooler. TDPs are pretty rough, but a 165w fan cooler on a 170w part doesn’t seem right. My 5800x runs hot AF despite coolers rated for significantly higher wattage parts. I have it running on custom water now, and it’s single CCX design means it still gets to 74c even on a 240x25mm and a 360x45mm rad equipped with T30 fans, which move assloads of air. Those hotspots are a killer.

We don’t have any measurements of what it was running at all day, so we can only speculate. But AMD runs a ton of volts out of the box if you don’t undervolt. You need good coolers.