Power Connector Theories

[The Gecko]

With the recent news about the burned/melted 12VHPWR connector on a RTX 4090, I started wondering why the industry continues to use (what looks to me as) variations upon the old Molex connector for newer, higher power uses. In my mind, Molex-style connectors have thin plastic walls and thin, easily damaged connectors. Furthermore, these connectors are always accompanied by numerous strands of low-flexibility 18 AWG wire. In comparison, the Radio Control Car/Truck/Plan/Quadcoptor industry has great connectors, capable of handing massive amounts of current, and they are always attached to highly-flexible wire of 16, 14, or 12 AWG wire. Wouldn't it just be better if the computer industry had said no to the 12VHPWR connector and used a pair of XT60 (or equivalent) connectors and a couple runs of high-strand-count soft-silicone 12 AWG wire for feeding high-power GPUs? Those Radio Control power connectors are vibration proof, grit & grime proof, made of high-temperature-resistant plastic, easily repairable, handle tons of current, get wedged into the weirdest and tightest spaces without issue, and can handle 1000+ insertions/disconnects unlike the 12VHPWR connector which is only rated for 30.

What are your thoughts?

 

[The Gecko]

Follow the Molex link above. Find the section talking about the venerable old 'AMP four-pin Mate-n-Lok', which we have all used. I can't believe this connector is still used today:

Despite its widespread adoption, the connector does have problems. It is difficult to remove because it is held in place by friction instead of a latch, and some poorly constructed connectors may have one or more pins detach from the connector during mating or de-mating. There is also a tendency for the loosely inserted pins on the male connector to skew out of alignment. The female sockets can spread, making the connection imperfect and subject to arcing. Standard practice is to check for any sign of blackening or browning on the white plastic shell, which would indicate the need to replace the arcing connector. In extreme cases the whole connector can melt due to the heat from arcing.

 

[BlueLineSwinger]

Inertia mostly, I believe. It's what the designers know. They already know all the suppliers/manufacturers who deal in such parts. It's familiar to end-users. And so on. Manufacture vs. RC-style connectors is probably somewhat simpler, as the contacts on molex-style connectors can cheaply/easily be machine crimped and RC-style connectors typically have to be soldered.

The issue with the new connector isn't necessarily that it's a poor or inadequate design (though that insertion rating is kinda low, few people will come neat hitting it). It a combination of builders not paying attention to proper technique, obsessive cable hiding, and ever-increasing GPU size coupled with often-shrinking cases. From appearances, the connector in the featured failure wasn't properly inserted fully or straight, and/or the bend of the wires coming out of it was too extreme, stressing the connection and making things worse. Had an RC-style connector been set up in the same way it too probably would have failed. (In typical usage, the battery connection in RC vehicles sits loose at the end of pigtails and is under very little stress other than some vibration. It's very hard to not have a straight connection.)

It's an interesting idea, though, and a type of change I probably wouldn't mind seeing (think of all the mainboard space it'd free up).

 

[bitbckt]

If any connectors need to be re-considered in 20-freakin-22, it's the 24-pin ATX and the front panel header.

The Micro-fit 6- or 8-pin could become Nano-fit - the intrepid folks over at AsRock Rack have snuck them into some products - and save some board room.

 

[BlueFox]

If any connectors need to be re-considered in 20-freakin-22, it's the 24-pin ATX and the front panel header.

The Micro-fit 6- or 8-pin could become Nano-fit - the intrepid folks over at AsRock Rack have snuck them into some products - and save some board room.

ATX12VO has been around a while.

 

[bitbckt]

ATX12VO has been around a while.

It sure has been. And three years later and some dozens of motherboards later, I have yet to see it in my hands. 12th gen seems like the first real opportunity, if I ever have a reason to buy one.

 

[BlueLineSwinger]

And ATX12VO really just drops lines for under- and unused voltages. The 12v lines are still carried over the same gauge wire using the same connectors as ATX.

 

[nabsltd]

though that insertion rating is kinda low, few people will come neat hitting it

If it becomes common because more cards want more power, then anybody testing video cards will hit that limit in a month.

 

[BlueLineSwinger]

If it becomes common because more cards want more power, then anybody testing video cards will hit that limit in a month.

Units used for testing are a tiny fraction of a percentage of total sales. Hopefully anyone doing testing would know enough to properly mind the connectors to extend the life and check for any signs of wear/failure. Very few people are doing anything beyond the initial install and maybe a disconnect/reconnect cycle or two every year depending on how thorough and meticulous they are about keeping the inside of their PC clean.

I consider myself typical for a PC builder. I'll take down my PC and clean it up, blow out the dust, etc. about every year or so. I can't recall ever having to dis/reconnect any of the internal power connections to do so. Only time that's happened is when I've had to replace storage or purchased a new GPU.

 

[T.Sharp]

I think it would be awesome to see XT connectors and silicone wire for GPUs and mainboards. One issues with high current draw and multi-pin connectors, is that any resistance difference between contacts / crimps / wire, will cause a load imbalance. Some pins can end up carrying a lot more current than others. Not an issue if you only have a single heavy gauge + and GND. Not to mention how much cleaner and simpler the cable management would be. Imagine a 12VO system with a single XT60 for the mainboard and single XT60 for GPU.

I would think that manufacturers could come up with a way to crimp XT connector pins, to keep things automated?