Nvidia investigating reports of RTX 4090 power cables burning or melting

Nvidia says it’s investigating two reports of RTX 4090 cards that have had power cables burn or melt. Reddit user reggie_gakil was the first to post details about their Gigabyte RTX 4090 issues yesterday, showing burn damage on the new 12VHPWR adapter cable that Nvidia ships with the RTX 4090. The connection on the actual card was also damaged and melted.

A second Reddit poster replied to the same thread showing off similar damage to an Asus RTX 4090 graphics card power connector.

“We are investigating the reports,” says Nvidia spokesperson Bryan Del Rizzo in a statement to The Verge. “We are in contact with the first owner and will be reaching out to the other for additional information.”

A melted RTX 4090 power connector.
A melted RTX 4090 power connector.
Image: reggie_gakil (Reddit)

Nvidia initially moved to this new 16-pin power connector for its own RTX 3090 Ti cards, and it has now become a standard on the RTX 40-series GPUs across vendors. There are concerns that the 12VHPWR power connector, which is designed for new ATX 3.0 power supplies, could cause issues if it’s bent a certain way.

The 12VHPWR connector and terminals are a lot smaller than the previous generation, and cable mod warnings that “it appears that bending the wires too close to the connector could result in some of the terminals coming loose or misaligning within the connector itself.” The site recommends not bending a connector vertically or horizontally, and instead having a minimum distance of 35mm from the connector before any bends occur.

That’s rather difficult in practice, with Nvidia’s adapter hitting the side panel in most modern cases. The original Reddit poster vertically mounted their RTX 4090, which means the cable could have bent before the minimum distance.

Burn damage to the power connector on the RTX 4090.
Burn damage to the power connector on the RTX 4090.
Image: reggie_gakil (Reddit)

YouTuber JayzTwoCents, who has been warning about this new connector for weeks, calls it “dangerous,” but says Nvidia doesn’t agree. “I think you’re worrying about issues that don’t exist,” said Brandon Bell, a senior technical marketing manager at Nvidia, in an email to Jay last month.

In early September, PCI-SIG — an industry consortium responsible for developing standards around peripheral component I/O data transfers — warned that some implementations of the 12VHPWR connector “have demonstrated thermal variance, which could result in safety issues under certain conditions.”

Images supplied by PCI-SIG show multiple ways a connector could melt or burn, and are the result of extreme bends during testing. The melting looks very similar to what has occurred with both of the Reddit posters’ RTX 4090 cards this week.

PCI-SIG's observations on 12VHPWR connectors.

PCI-SIG’s observations on 12VHPWR connectors.
Image: PCI-SIG

The solutions to these issues might be to avoid Nvidia’s power adapter altogether, or be very careful about how you position or bend it. It’s a bulky adapter that’s supplied with RTX 4090 cards, and needs up to four 8-pin power connectors. Power supply vendors are starting to ship 12VHPWR cables that ditch the bulky connector for a single cable that terminates into two 8-pin power connectors on a PSU. Corsair sells its own for $19.99.

These cables should help avoid the awkward bends we’re seeing with these new connectors, particularly against the sides of cases. New ATX 3.0 power supplies will help too, but there aren’t many on the market and not many PC gamers will want to spend extra to replace a working PSU just to get a native implementation of the 12VHPWR connector.