CableMod is recalling all 90deg and 180deg 12VHPWR adapters
PLANNED VOLUNTARY SAFETY RECALL OF CABLEMOD 12VHPWR ANGLED ADAPTERS, V1.0 and V1.1 – CableMod
the nvidia 12VHPWR shitstorm continues!
So, I haven't kept up on GPU news. I get that the connector isn't robust enough for certain systems, but why? I read the recall notice, and it talked about melting connectors.
The 12VHPWR specification in ATX3.0 was meant to simplify connections for ever-higher power PCIe devices. Instead of chaining multiple 6 or 8 pin connectors together, it provides a single 12pin connector (6 power, 6 ground) with 4 additional tag-along "sense pins" that allow the cable to communicate the power rating of itself and the power supply to the connected device. In theory it's sound engineering; allows only a single connector to run devices anywhere from 75W up to it's stated max of 600W.
The key is that the 12VHPWR spec really pushes the wire and connectors much closer to their safe limit in order to improve packaging and wire flexibility. For example, the old PCIe 8-pin spec officially only provides three 12V hot pins, each with one wire- the entire connector is rated for 150W, which means that each pin/wire is carrying only 50W, or 4.2 amps at 12V.
Comparing this to the 12VHPWR spec, there are 6 +12V and 6 ground pins/wires, meaning when running at it's max spec of 600W, each pin is carrying 100W, or 8.3 amps at 12V! This is DOUBLE the 8-pin per-pin spec, so we're already flying close to the sun on single 16gauge wires.
where the problem arises: the electrical connection between the male and female plugs in the 12VHPWR standard is mechanically flawed and can sometimes have too much resistance due to poor fit tolerances and slop in the clip/insertion guides. And by too much, I mean only a fraction of an ohm caused by a pin being 0.1mm undersized is enough to cause failure, especially when being run so close to it's design limits. When paired specifically with the RTX4090, which pulls 450W or more depending on OC settings, despite the plug supposedly being rated for 600W at 12V, this slightly high resistance causes a big heat buildup in the connecting pins and it melts the plastic connector housing. Melted plastic is Very Bad, it can start fires and damage/destroy the GPU.
CableMod was providing adapters that were meant to relieve the stress on the connector itself caused by trying to bend the wire around side panels, which theoretically would help with the poor contact melting problem. but due to manufacturing tolerances and existing flaws in the 12VHPWR spec they were also causing their own melting problems. Really, it's not even cablemods fault... but they got themselves stuck in the middle of it by choosing to make products for this segment.
I really appreciate the detailed info!
...too much resistance due to poor fit tolerances and slop in the clip/insertion guides. And by too much, I mean only a fraction of an ohm caused by a pin being 0.1mm undersized is enough to cause failure, especially when being run so close to it's design limits.
So, sounds like we need to graduate to bolt-on connectors or thicker wires. Maybe a mini breaker panel. h/j
Yeah if I got a card that required it I think I'll just straight solder the wires.
Isn't the newer 12v6x2 connector supposed to fix this? I think nvidia has been putting this on all new GPUs .
Eli5 but wouldn't going to 24v fix all of this? People buy new PSUs for their 4090 anyway.
Now I’m glad I was too lazy to ever install mine.
procrastinators win once again!
This standard by Nvidia must have been horribly rushed IMO if it's this hard to design one that won't melt
yeah, it's a sloppy standard with a lot of variance allowed for how close to electrical limits they were trying to run it... and the mechanical execution in manufacturing was clearly corner cut.