Zoom in / The RTX 4090 Power Adapter powers four 8-pin power connectors into one 12VHPWR connector.

Sam Mackovic

Earlier this week, several Reddit users reported that the power connectors for their expensive new Nvidia GeForce RTX 4090 GPUs had partially melted and that Nvidia was looking into the problem. Since then, at least nine additional Reddit users have posted about the same problem with the 16-pin power connector (a thread gathering all the information about the problem is here).

Igor Valosek of the German-language hardware site Igor’s Lab also has perform additional tests, and said that the power adapter cable (not the GPUs or the 12VHPWR connector) could be to blame for the problems. The adapter, which is apparently manufactured by a company called Astron and provided by Nvidia to all of its onboarding partners, uses “a total of four thick 14AWG wires spread over a total of six pins,” with thin solder that Wallossek says can be easily damaged when the cables are moved or bent.

The solder inside the Nvidia power adapter cable can be damaged if the cables are moved or bent too much.
Zoom in / The solder inside the Nvidia power adapter cable can be damaged if the cables are moved or bent too much.

“If, in the worst case, the two outer wires break, all the current in the middle flows through the other two wires,” Walosek wrote. “The fact that this gets really hot doesn’t need to be explained in isolation.”

Compare the Nvidia adapter cable to the 12VHPWR cable provided with the Be Quiet! Dark Power Pro 13 power supply, one of the few newer ones ATX 3.0 PSU models with a 12VHPWR cable that plugs directly into the PSU instead of relying on an adapter. The cable is thicker than the one in the Nvidia adapter because each pin has its own wire, but it also runs cool and provides reliable power to the GPU.

Wallossek also said that Nvidia has told its partners to send all affected cards back to Nvidia for further investigation and testing. We asked Nvidia about this issue and the investigation earlier this week and will update if we receive new information.

https://arstechnica.com/?p=1893799