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https://www.techpowerup.com/300338/nvid ... them-to-hq

NVIDIA is responding to reports of the 12+4 pin ATX 12VHPWR power connector of its new GeForce RTX 4090 "Ada" graphics cards being unreliable, and posing a potential fire hazard. The company has reportedly instructed its add-in card (AIC) partners, companies that sell custom-design graphics cards; to collect all retail graphics cards with burnt power connectors, and send them over directly to NVIDIA HQ for investigation. Reports of the 12VHPWR connectors overheating due to improper terminal contact aren't new, but this is the first time a retail product implementing the connector is experiencing reliability issues.

The Reddit user that reported this showed that both ends of the cable were burnt. I read in other news that AMD will be sticking with 8 pin connectors. I feel that the 16 pin cable for ATX 3.0 is just too small to handle the voltage spikes cards like the 4090 can pull. I'd hazard a guess that the cable is getting far too hot and causing a short.

Yes, it is too small. Just compare the surface area of just three 8 pin PCI-E connectors to that little thing.

That and that stupid adapter is just badly designed, with all the wires crammed into it. The custom ones made by PSU manufacturers and Cablemod is much better because they splice the cables before the connector.

I'm not saying it's not in spec, but having used molex connectors for decades (not just PCs, but in power amplifiers and ham radios equipment), I can tell you that just having the connector slightly cockeyed in the socket will cause resistance. Heck, I've seen 8 pin PCI-E connectors melt because they weren't properly seated, or there was a bit of crud on the contacts.

They should just go back to multiple 8 pins. They work. This extra complexity is not needed.

FYI: Jayz shows the NVidia adapter gets hotter than the Cablemod cable:

Igor's Lab PAINSTAKINGLY tore a cable apart to see how it was made. And now we know.

https://www.igorslab.de/en/adapter-of-t ... reakpoint/

The wires are soldered in the connector, not crimped. Rule #1 in electronics: an electrical solder joint is NOT a mechanical connection. It should never be relied on to take any strain. So bending the cable HORIZONTALLY (left-right) can break one of the end solder joints, and because the sense wire still thinks there's power on that pin (because the sense wire is still attached to the disconnected power line) the card continues to draw power. Apparently NVidia didn't bother to sense voltage on each pin on the card and just relied on the sense wires in the cable:

The right way to do this is the way PSU manufacturers and Cablemod is doing it: Crimp the wires at the connector, and place the splice farther back on the cable.

You can see the four power wires from each of the 8 pin power cables, soldered to metal tabs that break it out into the six power pins on the connector on the GPU in this photo from Igor's Lab. This is a really sloppy way to do this. Any bending is guaranteed to break one of the solder joints.

Here's what the Cable mod cable looks like. You see how the wires are spliced in a "Y" far away from the connector? This is also how the PSU manufacturer's are doing it.

SIGH
This has become quite the debacle.

There seems to be two different cables. One is built better. GamersNexus only has the 'good' cable, so they're asking people to send in a 'bad' ones. They're willing to pay for them.

It's still soldered, but uses 4 big solder pads instead of small ones on the end. I still say that it's stupid to solder these things. Waste of labor too. Better to crimp them and splice the cable.

NVIDIA 16-Pin Adapter Comes In Two Flavors, 300V Is Good For GeForce RTX 4090 But 150V Is A Fire Hazard
https://wccftech.com/nvidia-16-pin-adap ... re-hazard/

Oh man it's 1990's pinball machines all over again! Pinball machines from the late 80s to mid 90s suffered from burnt GI connectors. They were of the insulation displacement type and over time would cook them selves. Most of the machines I have I have done the upgrade to trifurcon connectors. This eliminates the bad connection and since its a good connections it never heats up and burns the connector.

You can google "burnt GI connector" and see some pictures of what happened. This seems like a very similar issue.

NVIDIA confirms there are two manufacturers of 12VHPWR power adapter cables

The discovery is a result of a long investigation that involved R&D teams from various board partners and NVIDIA themselves, as Gabriele Gorla (Director of Engineering at NVIDIA) was kind to share some further details. The company even provided a presentation that explains the differences between both types of cables.

It is said that the official NVIDIA 600W cable that is bundled with all GeForce RTX 4090 graphics cards was either manufactured by a company called Astron or NTK, both are Taiwanese companies that compete with each other. Igor discovered that the NTK cable has a better latching system, and it uses one spring contact, as opposed to Astron’s two-spring contact design.

https://videocardz.com/newz/nvidia-conf ... ter-cables

Steve figured out how to reliably melt the power adapters without overclocking. He even makes 'good' native psu cables melt, so the problem really does seem to be the connector design.

Just keeps getting worse.