Overclock.net › Forums › Cooling › Other Cooling Discussions › PWM, Fan Headers, Fan Xpert...Confused.
New Posts  All Forums:Forum Nav:

PWM, Fan Headers, Fan Xpert...Confused.

post #1 of 3
Thread Starter 
Hi All,

I wanted to control the fans in my case and on my H100 by temperature, which I believe that is what Fan Xpert does. PWM I gather works by load to the CPU, but I am unsure. I always used a controller, but I don't want to install one in my new case.

So a few questions:

Do I need PWM fans for the Fan Xpert to work?
Do I need to plug the PWM fans into the headers for the PWM feature to work?
Most reliable way (other than controller) to be silent at idle/light load, and only go as high as necessary at higher temps?
Does mobo undervolt them or does the fan get a constant 12v?
Would I be better off controling them in the uefi?

Any tips/help are appreciated.

Thanks in advance!

cheers.gif
Edited by Rmerwede - 9/11/13 at 11:04am
post #2 of 3
Assuming the mobo we're talking about is the ASUS Rampage IV Gene in your sig:

Quote:
Originally Posted by Rmerwede View Post

Do I need PWM fans for the Fan Xpert to work?

On the CPU_FAN and CPU_OPT headers, yes, I think the fan/s should be PWM for Fan Xpert to work OK.

On CHA_FAN 1-2-3 you can plug either 4-pin PWM or 3-pin fans and they will be controlled, but only by voltage and not by true PWM (in practice this means a higher min operating rpm and no possibility of fan stopping if so desired for PWM fans).
Quote:
Do I need to plug the PWM fans into the headers for the PWM feature to work?

Yes.

It will also work if only the tach and PWM wires go to the mobo CPU_FAN & CPU_OPT headers, while +12V and ground go direct to PSU.

Quote:
Most reliable way (other than controller) to be silent at idle/light load, and only go as high as necessary at higher temps?

FanXpert works perfect for me.

0370e022_FanXpert.png

Quote:
Does mobo undervolt them or does the fan get a constant 12v?

In this particular mobo:

4-pin PWM fans on CPU_FAN & CPU_OPT get a constant +12V and are "pulsed" thru PWM wire to regulate speed.

3-pin fans on CHA_FAN 1-2-3 are undervolted.

4-pin PWM fans on CHA_FAN 1-2-3 get a constant +5V thru PWM wire, and are undervolted thru +12V wire for speed (this is an ASUS trick to regulate PWM fans by voltage and not by true PWM on CHA_FAN headers).
Quote:
Would I be better off controling them in the uefi?

Better than nothing, but Fan Xpert allows finer control at your leisure.
HAL-9011
(14 items)
 
  
CPUMotherboardGraphicsRAM
Phenom II 960T X6 4.1GHz ASUS M4A89GTD Pro Radeon HD 6870 16 GB DDR3 1600MHz 8·8·8·24 
Hard DriveHard DriveHard DriveOptical Drive
OCZ Vertex 4 128GB OCZ Vertex 2 120GB WD Caviar Black 1TB LG DVD-RW 
CoolingCoolingOSOS
Noctua NH-D14 Accelero S1 R.2 + 2x NF-F12 Se7en x64 Se7en x32 
PowerCase
Antec TP-650W CM HAF 912 + 
  hide details  
Reply
HAL-9011
(14 items)
 
  
CPUMotherboardGraphicsRAM
Phenom II 960T X6 4.1GHz ASUS M4A89GTD Pro Radeon HD 6870 16 GB DDR3 1600MHz 8·8·8·24 
Hard DriveHard DriveHard DriveOptical Drive
OCZ Vertex 4 128GB OCZ Vertex 2 120GB WD Caviar Black 1TB LG DVD-RW 
CoolingCoolingOSOS
Noctua NH-D14 Accelero S1 R.2 + 2x NF-F12 Se7en x64 Se7en x32 
PowerCase
Antec TP-650W CM HAF 912 + 
  hide details  
Reply
post #3 of 3
Thread Starter 
Holy Crap TELVM!

Better than my RIVG manual! That answers all my questions... Great help, thanks a bunch!

cheers.gif
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Other Cooling Discussions
Overclock.net › Forums › Cooling › Other Cooling Discussions › PWM, Fan Headers, Fan Xpert...Confused.