Question Connecting PWM fan to DC fan connector

plunix

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Dec 17, 2005
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Hello, i just bought 3 phanteks t30. I plan to run them in the 3k rpm mode, at a 0.36A input current. Two intake, one exhaust.

Besides the cpu fan, my MSI z490m MAG has a pump fan (pwm) and 3x sys fan (dc) fan headers.

I want to know the best way to connect the 3 fans. The sysfan dc headers are 4pin but i thought dc mode was for 3pin connectors.

Why would the mobo headers labelled dc mode, have 4 pins?

Should i run 3 fans off the single pwm header or use the sys fan headers?

Should i get a fan hub and power them from the psu?

Thank you.
 
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Paperdoc

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Perhaps the manual is not quite clear enough. ALL of the fan headers on that mobo have 4 pins and ALL can be configured to use EITHER 3-pin Voltage Control Mode (aka DC Mode) OR the new PWM Mode. MSI just made a decision on which way to pre-set the default configurations of these headers. They set CPU_FAN and PUMP_FAN to PWM Mode, and the three SYS_FAN headers to DC Mode by default. But YOU can change any of those in BIOS Setup and SHOULD set them to match the fan type you plug in.

Since you have three SYS_FAN headers and plan three fans using max 0.36 A each, I suggest you connect one fan to each header to keep it simple. In BIOS Setup just configure all of those headers identically so all the fan will do the same thing. Referring to the diagram on manual p. 38, for these 4-pin PWM fans for case ventilation, click on the Set All Default at lower right, then set all to PWM Mode and to use the Motherboard temperature sensor, not the one inside the CPU chip.
 
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plunix

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Thanks. I'm currently daisy chained to the pump fan header because i read it has higher amps output, but couldn't verify that info. It seems to be working fine.

I had the temp sensor set to core temp. I'll have to see which sensor is for the motherboard.
 

Paperdoc

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If you are using that one PUMP_FAN header for all three fans, that will work IF you configfure it right. First, ensure that it is set to work with FANS, and not a pump. In the Pump option it will always run things full speed. Other than thar, configure as I suggested earlier.