After installing my 4090, reading all the articles, and watching the YouTube nonsense, I noticed something. I am wondering if some people are just plain not plugging in the connector to the card all the way in some cases. I thought mine was plugged in and before turning the system back on after some tinkering I gave it another check and sure enough it needed to be pushed in a little further to hear that very faint click. This connector doesn't have that definitive click like the eight pin connectors do currently. I physically checked the connector by holding a flashlight under the cable to notice this since the tab for this connector is there so this could easily be missed. Not taking anything away from the other theories about poor soldering and bending and whatnot, just a observation on my part.