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HELP!! Confusion on PWM Y-Cable

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#1
Hi everyone! I am the beginner of playing DIY on my own computer. I have searched the PWM Y-Cable in the market, they are only using in the mainboard. The PWM signal input from the mainboard is used to control a series of connected PWM fans for optimal performance in noise and cooling.

Now I come up some questions that need someone can fixed my confusion.

1) Why the PWM Y-Cable just used in mainboard, not in graphic card?
2) Is it necessary to input the signal from the GPU and make the RPM of VGA cooler and case fan at the same speed?
3) If it makes sense, why I cannot find the PWM Y-cable for graphic card?

That’s all I want to know. Thanks~
 
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#2
1) Generally speaking, graphics card coolers have their own attached fans, which are wired to plug directly into the graphics card, and don't usually support adding more fans (As always, there are some exceptions to the rule). Computer cases usually have many spots for fans, some of which may be left to be added later (spots on the case which support adding a fan, but does not include one)

2) No. You want the graphics card's fan speed to be set based on the GPU temperature, and the case fans to be set based on either the CPU or "system" temperature.

3) See #1. A GPU PWM Y-Cable would be a very rarely used cable. That said, it is technically possible to make one.

This leads me to wonder why you are asking. What is it you are trying to do?
 
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#3
2) No. You want the graphics card's fan speed to be set based on the GPU temperature, and the case fans to be set based on either the CPU or "system" temperature.

3) See #1. A GPU PWM Y-Cable would be a very rarely used cable. That said, it is technically possible to make one.

This leads me to wonder why you are asking. What is it you are trying to do?
I can see the need for such a cable, but I agree its use is rare. I, for example, have a 120mm fan pointed directly on my graphics cards, so I can see myself wanting to have its speed controlled by the graphics cards' temperatures rather than the system temperature.

That said, there are very almost no situations where graphics are being taxed but the CPU is idle, whereas the reverse is very common, so using the CPU PWM signal is a good compromise since you likely wouldn't have a situation with inadequate GPU cooling.
 
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#4
I think the main use for one of these is when you have one mobo CPU fan socket and 2 CPU fans. That's what I use mine for. GPU can handle its own fan speeds.

Beware when you do get one though, the signal wire should only be connected to one fan, if both are connected you get double the RPM reported which is no good. I had to mod my splitter cable.
 
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