Thursday, September 22nd 2022
8-pin PCIe to ATX 12VHPWR Adapter Included with RTX 40-series Graphics Cards Has a Limited Service-Life of 30 Connect-Disconnect Cycles
PSUs with native 12+4 pin ATX 12VHPWR connectors are few and far between, which means some of the first adopters of the GeForce RTX 4090 "Ada" graphics cards will rely on the adapter cable that converts 8-pin PCIe power connectors into one 12VHPWR connector that plugs into the graphics card. Cards that stick to the baseline specs include adapters that convert three 8-pin PCIe connectors (for 450 W output that matches the RTX 4090 reference specs); whereas some premium overclocked RTX 4090 cards, such as the ZOTAC RTX 4090 AMP Extreme, include adapters that convert as many as four 8-pin PCIe to a 12VHPWR, maxing out its 600 W power delivery capability. The product page of the ZOTAC AMP Extreme has an interesting sentence describing this in-box adapter: "Limited service life with up to 30 connect / disconnects."
Apparently the adapter is only good for up to 30 connect/disconnect cycles safely, before you'll need another one. For most gamers who'll install the card and forget about it for years, this shouldn't be an issue. However, for overclockers and enthusiasts using the card on an open-air bench and who rely on a lot of moving cards around, this could be an irritant. Tech journalists (reviewers) swap graphics cards out a lot, too, but then they're likely to have several such adapters lying around from multiple samples, or a PSU with a native 12+4 pin connector.
Our best guess is that this is a mechanical limitation assessed by NVIDIA for the maximum number of times the adapter can handle connection cycles before its contacts begin to wear out, and its safety is compromised. If you look closely at the picture above, the adapter has an NVIDIA logo, which means NVIDIA is directly supplying this adapter to AIC partners to include with their custom-design cards (and not counting on them to develop their own adapters). The 12VHPWR connector may look diminutive, but it's capable of delivering not just 600 W continuously, but also handle 200% excursions (brief spikes in power draw), which mean 1200 W. This is a lot of current (12 V, 100 A, enough to crank an automobile), and so NVIDIA isn't taking any chances with safety.
Source:
Wccftech
Apparently the adapter is only good for up to 30 connect/disconnect cycles safely, before you'll need another one. For most gamers who'll install the card and forget about it for years, this shouldn't be an issue. However, for overclockers and enthusiasts using the card on an open-air bench and who rely on a lot of moving cards around, this could be an irritant. Tech journalists (reviewers) swap graphics cards out a lot, too, but then they're likely to have several such adapters lying around from multiple samples, or a PSU with a native 12+4 pin connector.
124 Comments on 8-pin PCIe to ATX 12VHPWR Adapter Included with RTX 40-series Graphics Cards Has a Limited Service-Life of 30 Connect-Disconnect Cycles
LOTES PCI-Express slots are rated for 50 insertions as well.
For reference, here is a time stamp in a video where Steve and DB talk about the pump out effect (among other things):
I will say this: everyone here should buy a tube of dielectric grease.
It'll get 0 from me
I did a 100 piece CPK for 30 cycles of the 12VHPWR connector and saw negligible degradation of the connector's capability.
As someone else already point out: The Molex Mini-fit Jr. We all already use today is also rated at 30 cycles (unless you use HCS, which only some companies do).
This isn't news. It's a soap opera.
this is not new this is not different then pcie 8 pin
the adapter melting is happening because you are trying to BOND 9 12V pins and 9 GROUNDS to 6 12V pins and 6 GROUNDS (the 12VHPWR 12 pin connector has 6 power and 6 ground) which results in lots of resistance As bonding wires at the end is quiet terrible for electrical resistance and you add the smaller pin Diameter to that and boom stuff gets melty
this is possible todo safely but would require somebody engineer a pcb adapter with a big power and ground plane to spread the load and dissipate heat at the connector probably something the size of EVGAS power link and would need to contain a fairly heafy pcb with enough copper to handle the thermo-electrical load
there is nothing wrong with the 12 pin connector, the issue is the type of adapter cables used and the amount of conductors
Mini-fit HCS terminals support more current than the 12VHPWR connector's terminals (10A vs. 9.5A), so you don't need more than 12 conductors (therefore doesn't need to split to three 8-pins). Nvidia and AIBs are providing adapters with more than two 8-pin connectors because they don't know what your PSU comes with in terms of terminal quality and wire gauge, so they're covering all bases.
The "issue" with adapter cables was a story that was made up by wccftech and the Jayz re-reported with additional crying and eye rolls. The fact of the matter is, the connector with the problem that PCI-SIG was telling members about was the 12VHPWR connector. NOT the 8-pins: cultists.network/8815/melting-12vhpwr-connectors/
For the record: I work for a member of the consortium and am on that mailing list that leaked email was on and can confirm what's fact and what's fiction. Too bad wccftech, Jayz, etc. didn't bother to reach out to any industry people before spreading fake news.
do you know if the testing was done at 600W or 450W ?
but each 8 pin can only carry 150W per spec so really you need 4 for the full 600w right
Honestly, what the "press" has become lately makes me really, really sad.The testing was done after securing a < 30mm bend radius at the PSU. Room temp was 26°C. Temperatures were above spec after 2.5 hours at continuous 55A load and exhibited melting at 10 to 30 hours (multiple results of multiple samples tested). Root cause is suspected to be the terminals farthest from the inward bend are deflected away from the outer wall of the receptacle surface causing high resistance and therefore current demand increasing on pins of lower resistance.I don't know why everyone keeps saying that. Connector and terminal specification documents are publically available from every manufacturer.
The 150W "spec" comes from PCI-SIG, driven by Nvidia, as well. The had already defined that the reason for the 6-pin on a GPU was because the GPU needed 75 more watts of power than what the slot could deliver. Needs 150W? Put in a second 6-pin. But when cards started needing 225W additional, Nvidia thought it would be silly to put a third 6-pin on the card. So they asked PCI-SIG if they could put two sense pins on an 8-pin connector so, if grounded, the card would "know" that it was safe to demand 150W from a single connector.
Think about it logically. Surely you would expect 6 conductors on a mini-fit jr. connector to deliver more than the equal amount of power as 4 tiny pins in a PCIe slot. And you don't magically double the capacity of a 6 conductor connector by simply adding two sense pins. If you want to double the the capacity, you MORE THAN double the conductors. But that wasn't the goal here. The goal here was to specify the power demands of the card: 75W, 150W, 225W, 300W, so on.
The cheaper terminals, of reputable brands, use the brass w/ tin terminals with 18g wire. In a 2x4 configuration with 2x3 terminations, those terminals support 8A per conductor. So, your "typical" 6-pin PCIe, or even 8-pin PCIe (since it's still technically only 6 power conductors) is capable of 24A. So, at 11.4V (because we always work +/-5%), you're talking about 273.6W per connector. Fine for a 6-pin and 8-pin on the same cable, but not good for two 8-pins which is when they tell you not to daisy chain. It's also why Nvidia's squid adapter has three 8-pins and not just two.
Some manufacturers use mini-fit HCS terminals. These are rated at 10A per terminal in a 2x3 configuration. So using the same math, you have 342W per connector assuming voltages drop to 11.4V.
The cable Corsair made here: www.corsair.com/us/en/Categories/Products/Accessories-|-Parts/PC-Components/Power-Supplies/600W-PCIe-5-0-12VHPWR-Type-4-PSU-Power-Cable/p/CP-8920284 uses 6x mini-fit HCS terminals per 8-pin connector. So two of those type 4 connectors are capable of a total of 60A, which is, obviously, GREATER than the capability of the 12VHPWR connector.Nope. Not even poor pin connections in the adapters. Pin connections in the 12VHPWR connector itself.
Which is funny that JayZ noticed it... touched on it.... showed a picture of the connector melting... .but still went on about how it's the adapters fault. Yes... There's A LOT of tape wrapped around the 12VHPWR connector on the GPU side to limit the bend radius. Correct. To limit the bend radius at the 12VHPWR connector. Come on Jay... use your head... what does that have to do with the 8-pin or the fact that the cable you're holding is an adapter?????
He's telling people "you better buy a PSU that's ATX 3.0 (which to him means has the 12VHPWR connector on the modular interface)" which is LITERALLY the part that is melting!!!!!!!!