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I have 3 fans: intake, exhaust, and CPU heatsink. There are plenty headers on the motherboard for even more fans but I want to have all the fans to adjust their speed with the temperature like the CPU fan does. The CPU fan header is the only one with the option it seems. If I leave the power and RPM wires where they are on the intake and exhaust fans, cut just the PWM wire from those two fans, and attach all the PWM wires together at the CPU fan header, this should accomplish what I want? No issue running 3 fans off the pin or leaving the power and RPM on the other headers? Thanks.
 

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I have 3 fans: intake, exhaust, and CPU heatsink. There are plenty headers on the motherboard for even more fans but I want to have all the fans to adjust their speed with the temperature like the CPU fan does. The CPU fan header is the only one with the option it seems. If I leave the power and RPM wires where they are on the intake and exhaust fans, cut just the PWM wire from those two fans, and attach all the PWM wires together at the CPU fan header, this should accomplish what I want? No issue running 3 fans off the pin or leaving the power and RPM on the other headers? Thanks.

they are cheap PWM hubs that does this exactly.
https://www.newegg.ca/Product/Product.aspx?Item=N82E16811984004

by cutting and solering wires, it gets difficult to change a fan if you need it. + the risk to short something etc
 

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I have 3 fans: intake, exhaust, and CPU heatsink. There are plenty headers on the motherboard for even more fans but I want to have all the fans to adjust their speed with the temperature like the CPU fan does. The CPU fan header is the only one with the option it seems. If I leave the power and RPM wires where they are on the intake and exhaust fans, cut just the PWM wire from those two fans, and attach all the PWM wires together at the CPU fan header, this should accomplish what I want? No issue running 3 fans off the pin or leaving the power and RPM on the other headers? Thanks.
Since all of your fans are PWM, all you need is this - https://www.amazon.com/Silverstone-Technology-Sleeved-Splitter-CPF02/dp/B00HJOJS9O/ . It's under $5 with shipping.

The Phanteks that @neojack suggested takes a single PWM signal and turns it into variable voltage. While that will work, since you have PWM fans it is not necessary.
 

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Most motherboard headers are good for 1 amp. Unless you're planning on running multiple Vantec Tornados or FHP141s @ 100% I'd just run a cheap splitter personally.
 

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Discussion Starter #7
Thanks everyone. Just wanted to double check before breaking something. lol I saw those hubs and splitters but I was hoping to keep the RPM readout of all the fans.

What neojack said.

You might find this link of interest. It's about using multiple PWM fans on single PWM control pin.
http://www.overclock.net/forum/246-...s-better-cooling-airflow-cooler-fan-data.html




Perfect! This picture from the link is exactly what I was thinking except they pulled power straight from the power supply. Says 8-10 fans the signal becomes weak so I should have no issue with 3. I have a box full of random wires that surely has what I need to make the cable from. I think I'm going to replicate this.
 

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Thanks everyone. Just wanted to double check before breaking something. lol I saw those hubs and splitters but I was hoping to keep the RPM readout of all the fans.







Perfect! This picture from the link is exactly what I was thinking except they pulled power straight from the power supply. Says 8-10 fans the signal becomes weak so I should have no issue with 3. I have a box full of random wires that surely has what I need to make the cable from. I think I'm going to replicate this.
My bad. What neojack said about using a PWM hub, but as ciarlatano pointed out the Phanteks PWM hub is not a PWM fan hub. It is variable voltage fan hub using PWM signal to convert 12v to variable voltage based on load and % of PWM signal.
Link to how Phanteks PWM fan hub works:
http://www.overclock.net/forum/23772675-post65.html

A little about fans' running amp rating/load versus startup / stalled motor amp load .. startup load is 2-5 times more amps. So a fan rated 0.1amp running load will pull 0.2-0.5amps meaning 2x 0.1amp fans is all we can run on most motherboard fan headers rated 1 amp.

That is why the better PWM splitters and hubs draw their power from PSU instead of motherboard and why I drew that PWM fan splitter with PSU power.

So you have 1x intake fan which is needed to supply CPU cooler and 1x exhaust fan to draw the air out. So what is supply cool air for GPU cooler fans? :p I suggest you read post after the PWM one. It's about case airflow and how to set it all up for optimum cooling:
http://www.overclock.net/forum/22319249-post5.html
 
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