Programmer Creates 12VHPWR ‘Safety Mechanism’ for RTX 4090

A Reddit user created a custom monitoring program to monitor the connector temperature of 12VHPWR-equipped graphics cards like the RTX 4090 (one of the Best GPUs) that have earned a reputation for melting. The program utilizes a 10k sensor that measures the temperature of the connector to warn the user or protect the graphics card from potential damage.

According to the user, who goes by u/mamolengo, the only item you must buy is the sensor for his program to work. You can get them for as little as $8 to $10 on Amazon, and most motherboards have a header to support them. In the Reddit user’s case, he plugged his into his Corsair iCUE commander pro. 

Malmolego says the program will read the sensor data and can be programmed to trigger a fail-safe command when the connector temperature reaches a “certain level.” For instance, the app can be programmed to turn down the GPU power limit (like in MSI Afterburner), kill an application/game or shut down the computer immediately.

Monitoring the temperature of the 4090 connector before it melts from r/cablemod

Even though this system won’t fully resolve the melting problems that might occur on a 16-pin graphics card, it can, at the very least, give you a warning ahead of time to potentially prevent any damage. If you have not heard by now, the latest 12VHPWR 600W power connector utilized by most of Nvidia’s graphics cards has been known to melt under normal use, particularly by its most powerful graphics card, the RTX 4090.

Nvidia claims that user error is the source of the issues, as they are not fully plugging in the 16-pin power connector. However, PCI SIG is already developing a revised version of the 12VHPWR 16-pin connector, called the 12V-2×6 connector, that will reportedly fix the melting problems caused by the first version. Incidentally, Nvidia has taken some of the modifications done to the 12V-2×6 connector and applied them to the RTX 4070.

In the meantime, before Nvidia switches all of its GPUs to this new power connector — or the modified version on the RTX 4070 — Mamolengo’s little safety application can still be helpful for RTX 40-series owners. Depending on the situation, the application can be used to potentially prevent damage from legitimately bad connector insertions and damage that might come from the connector itself. In the case of the latter, users can report the high-temperature readings to the GPU manufacturer so that the card can get repaired under warranty.