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GPU fans power draw

void pointer
Go to solution Solved by RMTM,
18 minutes ago, void pointer said:

I've seen some GPU pcb breakdowns and there is usually a common layout that has VDDCI, VCORE, VMEM, VDISP now what I'm specifically wondering is to which of those is the gpu fan power connected to?. I know I'm talking about small percentages but I'm trying to determine if it would be marginally better to plug the gpu fans to the motherboard instead of the gpu for overclocking purposes, I'm using a kraken g12 so basically the two AIO fans can pull like 1 amp from a standard fan header at 12v that would be 12watts max per fan and that's quite significant for a 185watt card. I'm trying to not influence the power available for vcore and vmem by connecting an AIO pump and two 140mm fans with a spliter using this cable that I bought image.png.5ececbfb84bd7481c8e434d9584e498f.png

 

From what I've read the card is kinda power limited since it has a single 8 pin connector while other higher clocking models have either 8 and 6 pin or two 8 pin connectors.

 

 

edit: This thread kinda provides an example of what I'm talking about: https://www.reddit.com/r/overclocking/comments/5uiwm6/it_is_slightly_beneficial_to_externally_power_gpu/ddud2fd/

 

The GPUs are designed to power it's own fans. Even if your GPU has an additional fan headers, they are only for PWM fan support. AIO pumps should always be plugged to the motherboard and as specified in the AIO and motherboard specs. Just make sure that you have enough PSU power capacity and all your motherboard power pin cables are supplied with.

I've seen some GPU pcb breakdowns and there is usually a common layout that has VDDCI, VCORE, VMEM, VDISP now what I'm specifically wondering is to which of those is the gpu fan power connected to?. I know I'm talking about small percentages but I'm trying to determine if it would be marginally better to plug the gpu fans to the motherboard instead of the gpu for overclocking purposes, I'm using a kraken g12 so basically the two AIO fans can pull like 1 amp from a standard fan header at 12v that would be 12watts max per fan and that's quite significant for a 185watt card. I'm trying to not influence the power available for vcore and vmem by connecting an AIO pump and two 140mm fans with a spliter using this cable that I bought image.png.5ececbfb84bd7481c8e434d9584e498f.png

 

From what I've read the card is kinda power limited since it has a single 8 pin connector while other higher clocking models have either 8 and 6 pin or two 8 pin connectors.

 

 

edit: This thread kinda provides an example of what I'm talking about: https://www.reddit.com/r/overclocking/comments/5uiwm6/it_is_slightly_beneficial_to_externally_power_gpu/

 

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18 minutes ago, void pointer said:

I've seen some GPU pcb breakdowns and there is usually a common layout that has VDDCI, VCORE, VMEM, VDISP now what I'm specifically wondering is to which of those is the gpu fan power connected to?. I know I'm talking about small percentages but I'm trying to determine if it would be marginally better to plug the gpu fans to the motherboard instead of the gpu for overclocking purposes, I'm using a kraken g12 so basically the two AIO fans can pull like 1 amp from a standard fan header at 12v that would be 12watts max per fan and that's quite significant for a 185watt card. I'm trying to not influence the power available for vcore and vmem by connecting an AIO pump and two 140mm fans with a spliter using this cable that I bought image.png.5ececbfb84bd7481c8e434d9584e498f.png

 

From what I've read the card is kinda power limited since it has a single 8 pin connector while other higher clocking models have either 8 and 6 pin or two 8 pin connectors.

 

 

edit: This thread kinda provides an example of what I'm talking about: https://www.reddit.com/r/overclocking/comments/5uiwm6/it_is_slightly_beneficial_to_externally_power_gpu/ddud2fd/

 

The GPUs are designed to power it's own fans. Even if your GPU has an additional fan headers, they are only for PWM fan support. AIO pumps should always be plugged to the motherboard and as specified in the AIO and motherboard specs. Just make sure that you have enough PSU power capacity and all your motherboard power pin cables are supplied with.

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20 hours ago, RMTM said:

The GPUs are designed to power it's own fans. Even if your GPU has an additional fan headers, they are only for PWM fan support. AIO pumps should always be plugged to the motherboard and as specified in the AIO and motherboard specs. Just make sure that you have enough PSU power capacity and all your motherboard power pin cables are supplied with.

ok cool I will connect the pump to the motherboard after checking the manual for pump headers. 

 

A 140mm fan has to consume more power than the smaller GPU fans right? so that could be out of the design spec

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2 hours ago, void pointer said:

 

 

A 140mm fan has to consume more power than the smaller GPU fans right? so that could be out of the design spec

No, it is entirely depenent on the fan specs. For example, a 40mm server fan can consume much more than a standard 140mm case fan.

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6 hours ago, void pointer said:

ok cool I will connect the pump to the motherboard after checking the manual for pump headers. 

 

A 140mm fan has to consume more power than the smaller GPU fans right? so that could be out of the design spec

Agree on the pump plugged to the motherboard pump headers.

 

- on 140mm fans, not always the case. For smaller fans needs more spin time or rpm to move as much as its fan blades are designed to push or pull therefore they require a certain bigger amount of power to do so. Unlike bigger fans, like the 140mm fans, they are big enough to pull or push much air volume in lesser RPM. So they are usually of less power consuming but a bit higher in torque. Whereas, pressure fans could be another topic. And remember if fans are connected in parallel(like the daisy, extensions and stuff like that) - all connected fans' power rating should be added. Total power should not exceed the the rated headers(always consult your motherboard updated specs).

 

But for now, best for you to do is to check the specifications(usually printed on the box or in a manual inside the box) of the fans and pumps vs the motherboard headers' specs/capacities before you buy or use. Always check those power and voltage requirements first before doing so. So that you and your investments are protected from any harm or damage. As a rule of thumb, power source from any motherboard/board should always be higher specs than any of the pumps/AIOs that you are going to use. Following this will prevent any overload issues. And use your motherboard as a guide in acquiring any fans or pumps. Stay safe. Have fun!

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22 hours ago, Blue4130 said:

No, it is entirely depenent on the fan specs. For example, a 40mm server fan can consume much more than a standard 140mm case fan.

Ok good example! I will check the GPU fans for their specs and compare them with the 140mm fans specs.

 

18 hours ago, RMTM said:

Agree on the pump plugged to the motherboard pump headers.

 

- on 140mm fans, not always the case. For smaller fans needs more spin time or rpm to move as much as its fan blades are designed to push or pull therefore they require a certain bigger amount of power to do so. Unlike bigger fans, like the 140mm fans, they are big enough to pull or push much air volume in lesser RPM. So they are usually of less power consuming but a bit higher in torque. Whereas, pressure fans could be another topic. And remember if fans are connected in parallel(like the daisy, extensions and stuff like that) - all connected fans' power rating should be added. Total power should not exceed the the rated headers(always consult your motherboard updated specs).

 

But for now, best for you to do is to check the specifications(usually printed on the box or in a manual inside the box) of the fans and pumps vs the motherboard headers' specs/capacities before you buy or use. Always check those power and voltage requirements first before doing so. So that you and your investments are protected from any harm or damage. As a rule of thumb, power source from any motherboard/board should always be higher specs than any of the pumps/AIOs that you are going to use. Following this will prevent any overload issues. And use your motherboard as a guide in acquiring any fans or pumps. Stay safe. Have fun!

Will definitely do!

 

 

Thank you both for the informative comments, have a nice week!

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