Users themselves can be the source of problems with 12+4-pin 12VHPWR power connectors on GeForce RTX 4090 graphics cards. Corsair’s power supply expert, aka JonnyGuru, believes users are improperly plugging adapters or cables into the graphics card’s power connector, causing the connectors to melt.
Let’s briefly recall that shortly after the start of sales of GeForce RTX 4090 graphics cards, reports appeared on the Internet about the melting of the 12VHPWR power connectors. At first, it was thought that the inferior adapters that NVIDIA and its partners put in the kit for graphics cards were to blame. These adapters convert four 8-pin connectors into a new 12+4-pin connector. Later it turned out that when connecting a video card without an adapter, that is, directly to a modern PSU with a native 12V HPWR cable, the connector can melt. NVIDIA itself has only announced an investigation into the problem so far, but has not commented.
And now, JonnyGuru has theorized that users may not fully insert the 12+4 pin connector into the graphics card connector, which may cause connection problems, and this leads to increased resistance, increased temperature and melting of the connectors. This theory is not new and has not yet been 100% confirmed. Nevertheless, JonnyGuru told how exactly he came to the described version of events.
First, the expert connected the Corsair HX1500i power supply to the GeForce RTX 4090 graphics card through the mentioned adapter, but with only three 8-pin connectors, which should have provided a higher current and, accordingly, more heating. To replicate the problem and cause the connector to overheat, JonnyGuru started messing around with the connectors, specifically trying to break the solder strength. After the tests, everything remained in place, it was not so easy to break the plug, and the temperature did not exceed 53C.
The expert then examined all known cases of melted connectors, reviewed every published photo, and compared undamaged connections to those that had melted. As a result, the following conclusion was drawn:ANY 12V HPWR connector could potentially burn out as ANY of them could be difficult to insert. <..> VERY DIFFICULT to insert completely“.
The expert noted that in many cases the damaged connector was not fully connected to the graphics card – there was a small gap that could cause problems. JonnyGuru recommends users who are concerned about their GeForce RTX 4090 graphics cards to use an electrical contact lubricant that ensures better contact between the connector and the connector on the graphics card.
NVIDIA has not yet commented on the situation. Meanwhile, the PCI-SIG organization, which is responsible for certifying everything related to the PCIe standard, including power connectors, has issued a notice warning of the upcoming release of a new version of the 12+4-pin 12VHPWR connector indicates. The latest specification can be published as early as December 6, 2022.