[SOLVED] Exhaust fan replacement and motherboard voltage

Viorala

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May 20, 2019
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Hi. I need to replace my exhaust fan since the one that came with my very old case won't always run on start up. I was thinking of this one:

https://www.amazon.com/gp/product/B07CG2PGY6/ref=ewc_pr_img_1?smid=A1Z5H6ZGWCMTNX&psc=1

But somewhere along the line I got the idea that only one fan on the motherboard could be 12v and that would be my cpu fan. But also that any fan connecting to the motherboard needs to be 4 pin. The internet says 3 pin can work in a 4 pin connection but that would leave out the 12v pin out? It also says the rules are to use a 9v, but everyone uses 12v anyway. I just need to know what kind of fan to get that won't blow up my motherboard, lol.

Also I'm not sure if 1700 rpm is good or not, I think I've seen Corsairs that are higher but only a 120mm will fit in the exhaust fan spot. My current exhaust fan seems rather slow when it decides to work. It's slower than my cpu fan. Does that matter?

I'm also planning on getting 2 magnetic fans for general cooling purposes but that will probably be another post.
 
Solution
Gigabyte Z490 UD AC
The Gigabyte Z490 UD AC has 1 CPU fan header and 4 system fan headers. In each of those headers, you could safely connect up to 3 of those Noctua fans per fan header on that motherboard (fan splitter required).

Thanks for the info. I definitely feel like I'm overthinking this.
A little bit...but better safe than sorry...
By the way the Noctua NF-P12 has a pressure-optimised (high static pressure) design that works best for air-based CPU coolers and water cooling radiators.
The Noctua NF-S12B is designed for low-noise case cooling and PC case ventilation.
Hi. I need to replace my exhaust fan since the one that came with my very old case won't always run on start up. I was thinking of this one:

https://www.amazon.com/gp/product/B07CG2PGY6/ref=ewc_pr_img_1?smid=A1Z5H6ZGWCMTNX&psc=1

But somewhere along the line I got the idea that only one fan on the motherboard could be 12v and that would be my cpu fan. But also that any fan connecting to the motherboard needs to be 4 pin. The internet says 3 pin can work in a 4 pin connection but that would leave out the 12v pin out? It also says the rules are to use a 9v, but everyone uses 12v anyway. I just need to know what kind of fan to get that won't blow up my motherboard, lol.

Also I'm not sure if 1700 rpm is good or not, I think I've seen Corsairs that are higher but only a 120mm will fit in the exhaust fan spot. My current exhaust fan seems rather slow when it decides to work. It's slower than my cpu fan. Does that matter?

I'm also planning on getting 2 magnetic fans for general cooling purposes but that will probably be another post.
The extra 4th pin does not give extra voltage. It provides the option of a fully automatic speed control (PWM) via the motherboard's 4-pin PWM fan headers. You could set the speed fan to run depending on temperature

If you connect a 3-pin fan into a 4-pin header the fan speed can be control by reducing or increasing voltage...if voltage based speed control is supported...otherwise it will run at full speed.

Which motherboard model do you have?
 
Gigabyte Z490 UD AC
The Gigabyte Z490 UD AC has 1 CPU fan header and 4 system fan headers. In each of those headers, you could safely connect up to 3 of those Noctua fans per fan header on that motherboard (fan splitter required).

Thanks for the info. I definitely feel like I'm overthinking this.
A little bit...but better safe than sorry...
By the way the Noctua NF-P12 has a pressure-optimised (high static pressure) design that works best for air-based CPU coolers and water cooling radiators.
The Noctua NF-S12B is designed for low-noise case cooling and PC case ventilation.
 
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Solution