My new Asus board (z87-Pro) has 4 4pin fan headers on it for case fans. I was attempting to plug a high RPM Delta PWM fan into it and found that when plugged in to one of the case fan 4 pin headers on the board it would spin at 2000RPM turned all the way down. Normally when that fan was plugged in to a PWM header on my old board it could spin at 900RPM. After looking in the book for the motherboard the pinouts for all the fan headers other than the CPU fan show +5v on the pin that the PWM would normally be ran on so the fan headers are not for PWM. What gives? What is the extra +5v for on the end? I don't think I have ever seen a 4 pin fan that wasn't for PWM.
4 pin fan headers on motherboard that aren't PWM?
killeraxemannic
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My new Asus board (z87-Pro) has 4 4pin fan headers on it for case fans. I was attempting to plug a high RPM Delta PWM fan into it and found that when plugged in to one of the case fan 4 pin headers on the board it would spin at 2000RPM turned all the way down. Normally when that fan was plugged in to a PWM header on my old board it could spin at 900RPM. After looking in the book for the motherboard the pinouts for all the fan headers other than the CPU fan show +5v on the pin that the PWM would normally be ran on so the fan headers are not for PWM. What gives? What is the extra +5v for on the end? I don't think I have ever seen a 4 pin fan that wasn't for PWM.
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Yes they are not PWM controlled, they are voltage controlled. They can only go down to 40% of the maximum rpm (voltage).
I don't know why they made them 4 pin, it is pointless. They could be three pin and still perform the same function on PWM and non-PWM fans. Probably marketing.
I don't know why they made them 4 pin, it is pointless. They could be three pin and still perform the same function on PWM and non-PWM fans. Probably marketing.
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That is really disappointing. One of the reasons I bought this board over one of the other ones I was looking at was because it appeared to have all PWM headers for the case fans. Thankfully it has a second CPU fan header for an optional CPU fan so I can plug my second set of PWM fans into that header. I just won't be able to control them independently.
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CPU is the primary heat source and usually other motherboard components' heat follows CPU. If you want to make sure not to overload mobo with too many fans on CPU header just use a PWM splitter with molex/sata power from PSU like the Gelid 1-4 fan PWM splitter cable or Swiftech 8-way PWM splitter hub.
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you can also get a splitter to run more fans off of the CPU header:
http://www.performance-pcs.com/catalog/index.php?main_page=product_info&products_id=38706
http://www.performance-pcs.com/catalog/index.php?main_page=product_info&products_id=38706
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You can control the non-PWM 4 pin headers independent of the CPU fan headers, it is just by voltage so you will not be able to go as low in speed as PWM.
I don't have experience with that Motherboard, but it is probably like mine. The Chasis A header is this 4 pin voltage controlled based on the CPU temperature. Tied to this is the Chasis B 3 pin header, which follows the voltage applied to the Chasis A header, so it is also voltage controlled but not independent.
I don't have experience with that Motherboard, but it is probably like mine. The Chasis A header is this 4 pin voltage controlled based on the CPU temperature. Tied to this is the Chasis B 3 pin header, which follows the voltage applied to the Chasis A header, so it is also voltage controlled but not independent.
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Quote:
That's what I am using. I have 2 of the evercool PWM fan splitters with molex. One is running my 2 Delta fans for my H100i off the CPU fan header and now the second one is running my 3 front Deltas off the CPU_OPT header. The only problem is that I can't change the speed of each set of the fans independently. Setting it up this way works fine but it is not working the way I thought it would when I got the board.Originally Posted by doyll
CPU is the primary heat source and usually other motherboard components' heat follows CPU. If you want to make sure not to overload mobo with too many fans on CPU header just use a PWM splitter with molex/sata power from PSU like the Gelid 1-4 fan PWM splitter cable or Swiftech 8-way PWM splitter hub.
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Quote:
Some builds we also use PWM control from GPU PWM fan header to give added case airflow for GPU when it's working / playing hard.
All my builds have CPU fan header controlled PWM case fans. More and more builders are doing this to control case fans.Originally Posted by killeraxemannic
That's what I am using. I have 2 of the evercool PWM fan splitters with molex. One is running my 2 Delta fans for my H100i off the CPU fan header and now the second one is running my 3 front Deltas off the CPU_OPT header. The only problem is that I can't change the speed of each set of the fans independently. Setting it up this way works fine but it is not working the way I thought it would when I got the board.
Some builds we also use PWM control from GPU PWM fan header to give added case airflow for GPU when it's working / playing hard.
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How do you do the GPU control? Looks like my GPU's have proprietary plugs on them for the fans. It would be nice to have my front fans spin faster when the GPU heats up.Originally Posted by doyll
All my builds have CPU fan header controlled PWM case fans. More and more builders are doing this to control case fans.
Some builds we also use PWM control from GPU PWM fan header to give added case airflow for GPU when it's working / playing hard.
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I use the CPU PWM to control my CPU fans and the fans that are directly feeding/exhausting the CPU cooler.
I use the voltage controlled chassis fan headers to control other case fans with a different curve (but still based on CPU temperature). I'd rather control these independently and I don't care if the lower limit is 40% on these.
I think you would need to make a custom splitter/adaptor to run off of the GPU PWM. You would also need to power it off of the PSU - I would guess the GPU header doesn't support much amperage. I am sure if you dug in these forums youe would find a guide on how to do it.
I use the voltage controlled chassis fan headers to control other case fans with a different curve (but still based on CPU temperature). I'd rather control these independently and I don't care if the lower limit is 40% on these.
I think you would need to make a custom splitter/adaptor to run off of the GPU PWM. You would also need to power it off of the PSU - I would guess the GPU header doesn't support much amperage. I am sure if you dug in these forums youe would find a guide on how to do it.
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Ah. That doesn't work in my case because 40% power on a Delta beast fan is still 2000RPM and fairly loud. I will just keep using the CPU header for all my fans. That is working and doing what I need it to do for the most part.Originally Posted by GeneO
I use the CPU PWM to control my CPU fans and the fans that are directly feeding/exhausting the CPU cooler.
I use the voltage controlled chassis fan headers to control other case fans with a different curve (but still based on CPU temperature). I'd rather control these independently and I don't care if the lower limit is 40% on these.
I think you would need to make a custom splitter/adaptor to run off of the GPU PWM. You would also need to power it off of the PSU - I would guess the GPU header doesn't support much amperage. I am sure if you dug in these forums youe would find a guide on how to do it.
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Assuming you have standard GPU 4-pin PWM you can use an adapter like in first lin in my sig. My GTX580DCUII plug is truly proprietary but most use the normal GPU fan 4-pin pattern.Originally Posted by killeraxemannic
How do you do the GPU control? Looks like my GPU's have proprietary plugs on them for the fans. It would be nice to have my front fans spin faster when the GPU heats up.
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