NVIDIA RTX 50 SERIES - Technical/General Discussion

[Armageus]

Especially if it's a cable carried over from the 40 series as the 5090 draws up to 56 Amps through a (the newer)cable designed for 60 Amps.

56A.... that's 672 Watts. The Connector is specced for 684 Watts Max, so already it's gone from a frankly terrible 1.1 Safety factor to basically no safety factor.

And then we wonder why things are melting

16-pin 12VHPWR connector - Wikipedia

en.wikipedia.org

EDIT:
60A = 720 Watts? that over spec for the connector?

 

[Murphy]

OK in my head a busbar basically converts (from a logical point of view) multiple contacts into one. Maybe that helps explain what I'm saying?

And the point you're making is exactly my point Path of least resistance... increase resistance even slightly, and electricity will take other paths, which results in the load balancing I'm talking about.

I think my language is just not 100% technically right which is causing confusion.

It does however it's the direction/connections/input vs output that makes it into a bus/busbar. It's not just multiple contacts into one, it's a single source into multiple outputs.

Yea i get what you're saying as WRT resistance/heat and when i first saw the DB video the same thought occurred to me, however when i looked into what sort of resistance change you'd expect going from room temp to 100° most things i looked at, admittedly hard to find anything concrete, it appeared to be tiny when compared to the other factors involved.

e: Plus as the article tommybhoy posted...

Aris explains: "In general, the cable remains exactly the same. Only the connectors on the PSU and GPU side change from 12VHPWR to 12V-2x6, for PSUs that used the native 12+4 pin headers. There are no changes in the cables (they are just called now 12V-2x6 cables instead of 12VHPWR which can be confusing)."

So the cables themselves haven’t changed.

 

[Nitefly]

We asked a PSU expert which adapters or extensions are okay for the RTX 50-series. His answer: 'DO NOT BUY adapters or extenders, they can all be dangerous'

Spending $2,000 or more on a new GPU? Then get the right PSU and cables to go with it.

www.pcgamer.com

Short version:

Only use the supplied Cable shipped with your 50 series GPU.
Don't use any 3rd party cables:

Especially if it's a cable carried over from the 40 series as the 5090 draws up to 56 Amps through a (the newer) cable designed for 60 Amps.

Thanks for sharing - was the bit on 56 -> 60 Amps in the article? Sorry to ask but I didn't see this. The article read to me as if the cables are the same, as per the bulk of info available, but the main issue is that there can be mismatches when using cables that aren't supplied with the PSU... although even then I wish the article was clearer on mismatches - it keeps switching from the reporter to the expert and back, grr.

 

[Sinbad2000]

It does however it's the direction/connections/input vs output that makes it into a bus/busbar. It's not just multiple contacts into one, it's a single source into multiple outputs.

Yea i get what you're saying as WRT resistance/heat and when i first saw the DB video the same thought occurred to me, however when i looked into what sort of resistance change you'd expect going from room temp to 100° most things i looked at, admittedly hard to find anything concrete, it appeared to be tiny when compared to the other factors involved.

The temperature coefficient of resistance of copper is 0.004 - so an 80 degree rise in temperature gives a 0.32% increase in resistance. It is indeed very small, but all else being equal, should shunt some current to the parallel conductors at lower temperature.

I guess the key here is that not all else is equal, and understanding needs to be gained of where the extra resistance in/leading to/from the low-use wires comes from.

I couldn't see on the DB video whether the pins in the connector that were stupid hot were the same pins as the wires that got really hot.

 

[Jay85]

5090 FE in stock

 

[Murphy]

I guess the key here is that not all else is equal, and understanding needs to be gained of where the extra resistance in/leading to/from the low-use wires comes from.

True but then, at least my though was, you'd be getting into things like one connector making better contact than the others, if there's differences in the quality of copper used in the wires, slight changes in wire thickness, etc, etc.

At the end of the day things that shouldn't really need to be considered/accounted for in what is meant to be a connector to be used by everyday people.

 

[Sinbad2000]

True but then, at least my though was, you'd be getting into things like one connector making better contact than the others, if there's differences in the quality of copper used in the wires, slight changes in wire thickness, etc, etc.

At the end of the day things that shouldn't really need to be considered/accounted for in what is meant to be a connector to be used by everyday people.

100% agreed! This stuff should be idiot-proof, and have plenty of headroom. 10% is not nearly enough.

Is it time to perhaps move to 24VDC or even 48VDC for these massive loads?

 

[EuhenioP]

5090 FE in stock

Gone in seconds

 

[Cookie12]

5090 FE in stock

Not in the UK? Lots of drops in the EU though

 

[Jay-G25]

5090 FE in stock

uk drop ? i know eu been getting loads but not seen any uk drops

 

[Jay-G25]

Not in the UK? Lots of drops in the EU though

yeah just had one from Italy and France in the basket but they don't deliver to UK so no good

 

[tommybhoy]

@Armageus @Nitefly made a typo, it's not up to 56 A, it draws up to 53A I've changed it

The card's average power was 568 W and it peaked at 637 W—a current draw of 53 A.

 

[Armageus]

@Armageus @Nitefly made a typo, it's not up to 56 A, it draws up to 53A I've changed it

Still isn't great in the scheme of things

 

[Twinz]

We asked a PSU expert which adapters or extensions are okay for the RTX 50-series. His answer: 'DO NOT BUY adapters or extenders, they can all be dangerous'

Spending $2,000 or more on a new GPU? Then get the right PSU and cables to go with it.

www.pcgamer.com

Short version:

Only use the supplied Cable shipped with your 50 series GPU.
Don't use any 3rd party cables:

Especially if it's a cable carried over from the 40 series as the 5090 draws up to 56 53 Amps through a (the newer)cable designed for 60 Amps.

Isn't every PSU that comes with 12VHPWR connectors/ cables "third party"?

The fact that no one is concerned about all the random old PCIE 8-pin cables that get plugged into the supplied adapters speaks volumes about how crap the design of the 12VHPWR connector is.

12VHPWR cables must be anointed by Nvidia as worthy but the PCIE 8pin cables that we are supposed to plug into the adapters? Those are fine. Plug in any PCIE 8 pin cable from virtually any manufacturer and you're fine.

Buildzoid nailed it when he called the connector "12v high failure rate".

 

[philo-sofa]

Genuine question - if the Asus software can monitor the amperage down each core of the cable, then doesn't that mean there is some scope for safety measures? Or am I misunderstanding?

There is some scope for the top-tier ASUS cards. Their sensors aren't connected to any electrical equipment that can load balance, but the software can note that certain pins are misbalanced, and prompt the user to try and fix it, even warn them to shut the system down.

You can't expect the PSU to do the load balancing because it has no knowledge of what's been connected to it, things that use electricity draw power.

Not true. The PSU could be designed to be able to sense the current in each of the six live wires, and to load balance them. It doesn't need to know what its connected to, just the total load request and power going down each live wire.

 

[Armageus]

The fact that no one is concerned about all the random old PCIE 8-pin cables that get plugged into the supplied adapters speaks volumes about how crap the design of the 12VHPWR connector is.

12VHPWR cables must be anointed by Nvidia as worthy but the PCIE 8pin cables that we are supposed to plug into the adapters? Those are fine. Plug in any PCIE 8 pin cable from virtually any manufacturer and you're fine.

Because the 8 Pin PCI-E cables/connectors are so overspecced, even the worst quality ones are still more than enough.
4x PCI-E connectors is officially rated at 600W, but as per the link above in reality the limit is closer to double that, at 1152 Watts

 

[Twinz]

Because the 8 Pin PCI-E cables/connectors are so overspecced, even the worst quality ones are still more than enough.
4x PCI-E connectors is officially rated at 600W, but as per the link above in reality the limit is closer to double that, at 1152 Watts

That's why the old connectors are more reliable; a nice, fat saftey margin.

 

[gpuerrilla]

Unless nvidia change in gear over this, I would much prefer to rely on the PSU manufacturer to come up with something robust. Although the crazy thing is the older connector type didn't seem to have this issue. I am all for the design change of the 50 FE its making them more compact and innovative airflow, and connections that have less cabling. However this issue seems to be created by overlooking the new connector on many levels.

 

[Curtis vincent]

Gone in seconds

nah it was Germany

 

[Shaolin Chicken]

nah it was Germany

We may get one tomorrow, all being well.