Thought i’d share this here just because it’s interesting, but before I start let me point out that this is 100% my fault.
I used a dual pigtail power cable to feed a AMD 9070XT which has been re-inserted countless times as I have reconfigured my dev/test system while working on VFIO/Looking Glass, and different GPUs.
In short, the cause was worn out contacts, these cables are not designed to be re-inserted this many times and there is no doubt that this is the cause of this failure.
This is a Type 4 Corsair cable which was plugged into a Corsair HX1200. This is not an after-market cable, but one that was supplied with the PSU.

