As you know, NVIDIA has been having a lot of problems with its 12VHPWR power connector, which is used in the RTX 4090 and also in the RTX 4080. You have certainly seen RTX 4090s out of order after the power connector has suffered irreversible damage since it literally melts.
NVIDIA has therefore officially communicated, explaining that it has identified about fifty cases worldwide. The first investigations would highlight a bad installation of the adapter provided with each RTX 4090, whether with Founders Edition cards or partner cards. NVIDIA provides the adapter to its partners. NVIDIA recommends that you first plug the adapter into the graphics card to ensure that it is firmly and evenly plugged in, before inserting your graphics card into the motherboard. After that you only need to power the adapter with 4 8-pin connectors.
NVIDIA is still investigating to find a way to ensure that the adapter is properly plugged in before powering up the graphics card. In any case, NVIDIA is committed to warranty support for all RTX 4090s that have been affected and damaged by this issue. A story that is not yet entirely finished and that could lead to an adaptation of this 12VHPWR connector.