I cannot control my fans and they're going OTT!

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ok so I have some cool master fans, set to performance mode on the actual fan. These fans are connect with a pwm to the motherboard.

I an using a "ek-cable splitter 4 fan pwm extended". This connects my fans and motherboard and also has a molex connected for extra power.

I have been onto my asus suite and changed the fan speed down and this does nothing.

I have just had a brain wave, could this be because on the splitter the pwm isn't working and the fans are running full power from the molex?
 
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Ok so I have tried another splitter and I am still getting the same problem, the fans are spinning at full rpm. I have gone onto the computer and turn them down manually to say 20% and this does nothing.

Anyone got any ideas what I could do?
These are 4 pin pwm
 
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This requires needle pliers and a bit of dexterity. Swapping the 0V pin for the 5V pin in the molex, you end up with 7V across the two pins supplying the fan power. (12V - 5V = 7V).
 
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So what I did was move the 4pin from cha1 header to the cpu fan header, and it's worked perfectly, but I need it to work on the cha1.


So does this probably mean the bios is setup wrong?
I'm using a asus motherboard, I also use asus fan expert. when I use fan expert I set my fans to go down to 20% and it doesn't do anything from cha1, the fans just stay at 100% (2800rpm).

So then I opened up my bios and under cha1 it says manual, so I changed this just to standard to see what happens, turned the computer off and on and it did nothing. Went back onto bios it says standard and doesn't change the fan speed.

My cpu is saying down at like 20-30 degrees, my motherboard about 30-40. The only thing that can be getting hot is the gpu but that's in the watercooling loop with the cpu.



Could there be anything I'm missing in the bios that is stopping me from changing the fan speed on cha1?
 
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So what I did was move the 4pin from cha1 header to the cpu fan header, and it's worked perfectly, but I need it to work on the cha1.

It is designed to synch up to 3 fans with the (4th) CPU fan/CPU temperature, so that's probably why it worked perfectly with the CPU fan header.

It is interesting that you say you need it to work on Cha_1. Why? Is it because you have another fan plugged directly into the CPU_Fan header normally? That's not really the way to use this splitter (even if a workaround can be found).

We really need more details. Which motherboard. Which CoolerMaster fans. How many exactly in total (including other type of fans/pump cable)?

Could you also please address what HoneyBadger asked?
 
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Ok so the computer spec:

Motherboard:p8P67
8x Fans: 120mm Cooler Master MasterFan Pro 120 Air Pressure
2x EK-Cable Splitter 4-Fan PWM Extended
Pump: DDC
Waterloop incoudes overclocked i7 and a 1080 gpu.

On the bios the pwm header should be set up as it is enabled and set to standard.

The reason I wanted to have the cha1 working was because I was going to have 4 fans on my CPU header and 4 fans on my cha1 using the 4 way splitters for each. I have a monster rad which is 85mm thick and needs a high amount of static pressure. So I have 4 fans either side.

I am using an open air case, thermaltake p5, so the motherboard doesn't get any cooling so I'm wondering if this is why the cha1 is running so high.


What would probably solve this is if I just got another splitter and have all 8 fans on the cpu fan header and set it to automatically cool the rad. Would it be a bad idea to have 8 fans on 1 header?

 
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Alright. This is why knowing which motherboard is helpful. According to the manual - http://dlcdnet.asus.com/pub/ASUS/mb/LGA1155/P8P67/E5940_P8P67.zip the CHA_1 fan header is not PWM. It is four-pin but as with many older motherboards only the CPU_FAN header is true PWM. The clue in the manual (it doesn't say it outright) on Page 2-25 is that the first pin on the CHA_1 header is for +5v, whereas for the CPU_FAN header the first pin is for "CPU FAN PWM".

The board has a CPU_FAN four-pin PWM header, a CHA_1 four-pin non-PWM header and a CHA_2 three-pin header. The CPU_FAN header supports a maximum of 1 Amp or 12 Watts. That doesn't matter too much if you find a way to use another splitter that is powered by molex or SATA.

A CoolerMaster MasterFan Pro 120 Air Pressure consumes a max of 2.16 Watts. http://www.coolermaster.com/cooling/case-fan/masterfan-pro-120-ap/

So, you could experiment with daisy chaining (somehow) a second similar splitter but the chances of success are slim, imo.

Given the scenario, I'd go with a PWM hub like the Silverstone CPF04 1-to-8 PWM Fan Hub. Never used it personally but has good reviews on sites like Newegg. Has proper four-pin headers for all 8 PWM fans, unlike the Phanteks PWM Hub which has three-pin headers and only six headers, requiring an extra splitter or two. http://silverstonetek.com/product.php?pid=526&area=en
 
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Wow that's a really good reply thanks for the help! That should have sorted it! I thunk that hud should easy be the best way around things! Really appreciate the help thanks.
 
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8x Fans: 120mm Cooler Master MasterFan Pro 120 Air Pressure

have a monster rad which is 85mm thick and needs a high amount of static pressure.
If you want quiet PC next time stay away from highest speed noise makers.
Many high speed fans don't even have that low minimum speed and also their motor (made for high speed) can keep extra noises at low speed.

And fan's pressure output (/airflow) drops anyway with speed so you don't win anything by using high speed fan heavily throttled down compared to moderate speed fan.
 
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