Info 12VHPWR PSA on cable bending

Leeea

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Apr 3, 2020
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See:
We suggest a minimum distance of 35mm from the connector before any bends occur.
1.3 inchs straight out of the connector, and

The 12VHPWR connector and the terminals used in it are much smaller than the previous generation. Through our extensive testing, 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. This may lead to an uneven load across the other wires, increasing the risk of overheating damage. The risk of this is substantially higher if the bend is done horizontally in relation to the connector orientation (left to right).
Do not bend horizontally.


This might seem obvious to all of you, but it was news to me. I would have made the same mistake this guy did:

I have done some pretty extreem bends with 8 pin connectors in cramped ITX cases. Sooner or later this would have zapped me.
 

Aikouka

Lifer
Nov 27, 2001
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See:

1.3 inchs straight out of the connector, and

Do not bend horizontally.

This might seem obvious to all of you, but it was news to me. I would have made the same mistake this guy did:

I have done some pretty extreem bends with 8 pin connectors in cramped ITX cases. Sooner or later this would have zapped me.
I'm still waiting on my CableMod cables (including one of the new 12VHPWR cables) to hook up my 4090. (They ship from China, so it'll take a bit.) Fortunately, since I'll water cool mine (once I can get a block), I'll have it vertically mounted (like my existing card) and I'll just run the cable up a bit and then start the bend. Although, if we're just talking about avoiding strain, the strain might not be so bad if the cable is going straight up? Until I get the water block, I'm not sure if I'll want to vertically mount it since that'll likely put it too close to the edge. I'll likely need to go horizontal, but I'd like to assume that my Meshify 2 XL has enough space!

Although, I really hope that their imagery isn't accurate. I assumed that the part with the CableMod logo on the 12VHPWR cable helped provide strain relief. However, if we look at the vertical images, it appears to be separate and likely just cosmetic. There (likely) wouldn't be an issue with bending the cable as soon as shown in the no-no vertical image if that piece provided strain relief.
 
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Leeea

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I'll have it vertically mounted (like my existing card) and I'll just run the cable up a bit and then start the bend.
That is exactly the configuration the guy in the video had with the failed connector and ruined 4090.
 

Stuka87

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Dec 10, 2010
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The connector is unlikely to be going anywhere, as its a PCIe 5 standard. And nVidia didn't invent it, this is Intel's doing.

The issue now is no few PSU's support it. Once they go, you won't need this dongle. It will just be one group of wires from the PSU to GPU.

There certainly should have been 90 degree power adapters though. Or better yet, don't put the power connector on the top of the car at all. The thing is so big, the power adapter HASD to be bent sharp to clear the side panel of the case, unless its mounted vertically.
 
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Stuka87

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Going off his photo, it almost looks like power draw is not being evenly distributed, and some pins are having higher draw than others. This would require some testing with a power analyzer to verify, but its worth somebody looking into.
 

adamge

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Aug 15, 2022
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Going off his photo, it almost looks like power draw is not being evenly distributed, and some pins are having higher draw than others. This would require some testing with a power analyzer to verify, but its worth somebody looking into.
The guy in the youtube video posted above points out that the connector's manufacturer says precisely this.
 

Aikouka

Lifer
Nov 27, 2001
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That is exactly the configuration the guy in the video had with the failed connector and ruined 4090.
Hm, I haven't had a chance to watch the video yet, but I'll have to see if it shows what exactly the guy did. I would suspect that a bad bend would lead to the adapter being ruined (via damaged internal cables) rather than causing it to melt down. It makes me wonder if it's plausible that there are faulty adapters? I'd also guess that someone could be pigtailin' it, but I wouldn't expect it to melt at the 12VHPWR side in that case.

In that case, I don't know if having a pure cable setup from the PSU to the GPU would be better than the adapter method.

EDIT:

Actually, what would happen if one of the pins at the 12VHPWR side was damaged? Would it still attempt to pull the same amperage through the remaining pins? PCI-E connectors have 3 12V pins, so it would be like pulling 150W over 2 pins instead of 3.
 
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CP5670

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Jun 24, 2004
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The real problem is the placement of the connector in the middle of the card. It should be in the back, facing the back. The Quadro/Tesla cards seem to have it like that.

I got the Corsair cable for connecting this plug directly to the PSU, but it's also straight and not 90 degrees. I think it should fit ok in my case though.
 
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mindless1

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Actually, what would happen if one of the pins at the 12VHPWR side was damaged? Would it still attempt to pull the same amperage through the remaining pins? PCI-E connectors have 3 12V pins, so it would be like pulling 150W over 2 pins instead of 3.
Yes, except potentially worse in that it may still be drawing some power over the 3rd pin but that conduction on 3rd pin now at high resistance which creates heat.

It could be worse. When you have more resistance from only two wires, this drops the voltage a little but since it is feeding buck regulator VRMs, they will need a little more current at the little lower input voltage, to produce the same output power.
 
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DooKey

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Nov 9, 2005
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Even 8-pin PCIe connectors have had failures like this. Not sure this isn't anything other than user error or simply a bad plug. Stuff happens. When we see droves of them coming in then we might be able to assume this is an issue.

IOW, put down the pitchforks for now.
 
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sze5003

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Good thing this guy's house did not burn down.

https://www.reddit.com/r/nvidia/comments/yc6g3u
I've got a 13900k, board and ddr5 ram ready just waiting for my nzxt bracket to ship for lga 1700.

I was looking forward to trying to get a 4090 this week from my microcenter. But not after this issue maybe I'll wait for a statement to be released or something. With how thick those cards are and where the connector is located it's almost impossible not to bend the cables unless you leave your glass panel off.

Cable mod sells the extension cables for 12vpwr but I wouldn't use extensions for something that pulls 600w. Probably need the direct custom cables for your PSU.

I recently got an EVGA G6 1000w last year right after I got the 3080ti so I would hate to have to buy a new one already.
 

AdamK47

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I've burned an ATX 12V connector on an X58 motherboard back in the day. This is when I was doing 3-way SLI. Too much current going through to the PCI-E slots. It didn't kill it. The connector was a little charred. I modded it by soldering on an extra molex connector to the 12V pins on the back of the motherboard.
 

DooKey

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So far so good for me with my glass panel installed. I made sure the plug stayed straight and gently bent the cable down with no pressure on the plug. So far (cross my fingers) my 4090 is running well.

With that said, I plan on buying the 90-degree cablemod cable.
 
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amenx

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Surprised this issue was not raised with the 3090 since its not far off the 4090 in power draw (esp with AIB cards).
 
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BFG10K

Lifer
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LOL, here it comes bois, I coin it pin-gate:


He says due to the ridiculous height of 4090, virtually no case allows 35mm clearance for Founder's Edition (AIBs are even taller) unless you mount it vertically.

This...is...literally...a...heater. Heaters can't be tipped over either.

Then he showed a screenshot of Jonnyguru saying cables were melting during testing. Comedy gold.
 
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DeathReborn

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Oct 11, 2005
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Aris puts a 12VHPWR cable through testing. He said old 12 pin hit 100c and was fine, 12+4 Straight 55c, Bent 57c. 505W sustained and he's not concerned, suggests poor connection increasing resistance and therefore more Amperes flowing through a poor connection. Could it be just a bad batch of cables, user error plugging the card in? He is going to do more tests when Asus send him a 4090 and using proper methodology reach a conclusion that isn't a knee jerk "Ngreedia bad" but a reasoned data led reason.
 
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