Sounds to me like it does not have a 12VHPWR that conforms to the standard. Would have to look closer at the 12VHPWR connector to determine it it has the 4 sensing pins or not, and if they are linked to the PSU or not.
It's very odd to me that they would use extension cables rather than cables that have the correct length...
Re: the 4 sensing pins cannot operate since it's a adaptor rather than a true 12VHPWR cable
It is common practice to use new adapter cable for existing modular psu. Corsair uses two type 4 gpu connector on psu end of adapter cable and 12VHPWR connector w 2 sense pins on gpu end. 1 sense pin is wired from each 8 pin type gpu connector (psu side).
I just bought from Aliexpress a cable for my RTX 4080 FE. It's a 12VHPWR connector on one end and two 8-pins connectors on the other end, each connector with 6 pins connected (3 positives and 3 negatives), and 2 free pins.
The sense pins are just jumped from negative wires.
I'm using this cable for a week now, and it's working great. No issues so far.
600W PCIe 5.0 12VHPWR Type-4 PSU Power Cable For Corsair Modular Dual 8pin to 16pin PCI-e Gen 5.0
WHY DOES NVIDIA adapter cable USE FOUR 8-PIN CONNECTORS, WHILE OTHERS, LIKE CORSAIR’S AND SEASONIC’S, ONLY USE TWO?
The 12VHPWR connector supports 16g wire. But not every PSU maker uses 16g wire for their PCIe cables. So Nvidia takes into consideration that user might be using some cheaper PSU with sub-standard cables and wants to make sure the problem is not on their end. (courtesy: Jonny guru)
Pretty bad decision to make your flagship rig with a 13900KF perform worse than the last years model; especially when you're running games.
The setup they have is ridiculous and looks like someone that didn't know what they were doing is the one who did all the settings for the CPU i.e. power, wattage, etc.
You can do PL1/PL2 at either 253w or 300w, give it a -0.050v undervolt and get good temps with great performance. Unfortunately, they decided to gimp the CPU dramatically even for gaming. Guessing around 20%. Heck you don't even have to undervolt it. Just a 300w on PL1/2 decent fan curve on a 240mm AIO will still work fine with benchmarks and gaming.
Yes, but without a proper PSU connection the sensing pins cannot communicate with the PSU, and that is the whole point of those pins.
Remember the connectors that caught fire. because they were not plugged in correctly to the video card, and caused the full load over a bad connection, causing the connector to fail and melt?
Well, one of the sensing pins is there to detect improper insert into the video card socket. If it's not properly inserted, the sensing pin will not make contact, and the PSU will get the signal it's not properly inserted and shut power delivery down.
That will not happen with an extension cable to a regular PSU.
side band sense pin S1 and S2 are there to prevent relatively low capacity psu from being overloaded by a high TDP gpu and causing system shut down/restart. That was the idea behind these sense pins. If the 12CHPWR connector installed is not completely flush and latch securely locked, the electrical interface of the high current 12V wires may experience high resistance above design safety and burn the plastic. This does not mean the side band sense pins would necessarily wiggle out of connection at the same time and lose electrical contact to Gnd and definitely send a feedback signal to tell a smart psu to shut down. If both sense pins did lose contact to gpu and become open, the gpu would react by drawing maximum 150w like a regular PCIe 6+2 pin.
to have the full power of 600W out of the 12VHPWR connector, both Sense 0/1 pins must be grounded. On the other hand, if these pins are both open, then the maximum sustainable power is only 150W, the same with the plain PCIe 6+2 connector. If the graphics card doesn’t find these pins, it will assume they are both open, so 150W max.
Re: the 4 sensing pins cannot operate since it's a adaptor rather than a true 12VHPWR cable
It is common practice to use new adapter cable for existing modular psu. Corsair uses two type 4 gpu connector on psu end of adapter cable and 12VHPWR connector w 2 sense pins on gpu end. 1 sense pin is wired from each 8 pin type gpu connector (psu side).
I just bought from Aliexpress a cable for my RTX 4080 FE. It's a 12VHPWR connector on one end and two 8-pins connectors on the other end, each connector with 6 pins connected (3 positives and 3 negatives), and 2 free pins.
The sense pins are just jumped from negative wires.
I'm using this cable for a week now, and it's working great. No issues so far.
600W PCIe 5.0 12VHPWR Type-4 PSU Power Cable For Corsair Modular Dual 8pin to 16pin PCI-e Gen 5.0
WHY DOES NVIDIA adapter cable USE FOUR 8-PIN CONNECTORS, WHILE OTHERS, LIKE CORSAIR’S AND SEASONIC’S, ONLY USE TWO?
The 12VHPWR connector supports 16g wire. But not every PSU maker uses 16g wire for their PCIe cables. So Nvidia takes into consideration that user might be using some cheaper PSU with sub-standard cables and wants to make sure the problem is not on their end. (courtesy: Jonny guru)
ProfessorW00d
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January 27th, 2023 15:00
Mumblin' Steve is sponsored by Corsair.
Vanadiel
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January 27th, 2023 16:00
Sounds to me like it does not have a 12VHPWR that conforms to the standard. Would have to look closer at the 12VHPWR connector to determine it it has the 4 sensing pins or not, and if they are linked to the PSU or not.
It's very odd to me that they would use extension cables rather than cables that have the correct length...
redxps630
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January 27th, 2023 19:00
one can see the Dell 12 pin extension cable has two tiny sense pins (S1-2). It looks similar to Corsair HX1500i cable.
F34R
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January 27th, 2023 20:00
You know there's an issue when your 13900KF doesn't perform as well as your 12900KF.
Vanadiel
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January 28th, 2023 07:00
Likely a design decision.
redxps630
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January 28th, 2023 12:00
Re: the 4 sensing pins cannot operate since it's a adaptor rather than a true 12VHPWR cable
It is common practice to use new adapter cable for existing modular psu. Corsair uses two type 4 gpu connector on psu end of adapter cable and 12VHPWR connector w 2 sense pins on gpu end. 1 sense pin is wired from each 8 pin type gpu connector (psu side).
One user recent feedback:
I just bought from Aliexpress a cable for my RTX 4080 FE. It's a 12VHPWR connector on one end and two 8-pins connectors on the other end, each connector with 6 pins connected (3 positives and 3 negatives), and 2 free pins.
The sense pins are just jumped from negative wires.
I'm using this cable for a week now, and it's working great. No issues so far.
600W PCIe 5.0 12VHPWR Type-4 PSU Power Cable For Corsair Modular Dual 8pin to 16pin PCI-e Gen 5.0
WHY DOES NVIDIA adapter cable USE FOUR 8-PIN CONNECTORS, WHILE OTHERS, LIKE CORSAIR’S AND SEASONIC’S, ONLY USE TWO?
The 12VHPWR connector supports 16g wire. But not every PSU maker uses 16g wire for their PCIe cables. So Nvidia takes into consideration that user might be using some cheaper PSU with sub-standard cables and wants to make sure the problem is not on their end. (courtesy: Jonny guru)
Jupiter_7
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January 28th, 2023 16:00
Alienware uses only Two 8-pin cables of 18-guage wire, they seem to think its fine for 600 watts?
F34R
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January 28th, 2023 17:00
Pretty bad decision to make your flagship rig with a 13900KF perform worse than the last years model; especially when you're running games.
The setup they have is ridiculous and looks like someone that didn't know what they were doing is the one who did all the settings for the CPU i.e. power, wattage, etc.
You can do PL1/PL2 at either 253w or 300w, give it a -0.050v undervolt and get good temps with great performance. Unfortunately, they decided to gimp the CPU dramatically even for gaming. Guessing around 20%. Heck you don't even have to undervolt it. Just a 300w on PL1/2 decent fan curve on a 240mm AIO will still work fine with benchmarks and gaming.
redxps630
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January 28th, 2023 18:00
18 and 16 AWG seem to have same max current rating
Vanadiel
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January 29th, 2023 09:00
Yes, but without a proper PSU connection the sensing pins cannot communicate with the PSU, and that is the whole point of those pins.
Remember the connectors that caught fire. because they were not plugged in correctly to the video card, and caused the full load over a bad connection, causing the connector to fail and melt?
Well, one of the sensing pins is there to detect improper insert into the video card socket. If it's not properly inserted, the sensing pin will not make contact, and the PSU will get the signal it's not properly inserted and shut power delivery down.
That will not happen with an extension cable to a regular PSU.
redxps630
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January 29th, 2023 10:00
side band sense pin S1 and S2 are there to prevent relatively low capacity psu from being overloaded by a high TDP gpu and causing system shut down/restart. That was the idea behind these sense pins. If the 12CHPWR connector installed is not completely flush and latch securely locked, the electrical interface of the high current 12V wires may experience high resistance above design safety and burn the plastic. This does not mean the side band sense pins would necessarily wiggle out of connection at the same time and lose electrical contact to Gnd and definitely send a feedback signal to tell a smart psu to shut down. If both sense pins did lose contact to gpu and become open, the gpu would react by drawing maximum 150w like a regular PCIe 6+2 pin.
to have the full power of 600W out of the 12VHPWR connector, both Sense 0/1 pins must be grounded. On the other hand, if these pins are both open, then the maximum sustainable power is only 150W, the same with the plain PCIe 6+2 connector. If the graphics card doesn’t find these pins, it will assume they are both open, so 150W max.
pdschweitzer
436 Posts
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March 29th, 2023 04:00
What is the Dell part number for this special 12 pin extension cable needed to add a 4080 or 4090 card?
pdschweitzer
436 Posts
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March 29th, 2023 04:00
What is the link where you puchased this cable?