CPU OPT fan settings

[Nonsensical86]

Hi guys,

I've bought a second 4 pin header fan to hook it up to my CM Hyper 212X and connect it to the CPU_OPT on my motherboard (Asus H97 Pro Gamer). However, the option fan is only running between 500 to 550 rpm. I would like the option fan to go a bit faster and i cannot find any settings to control it either in the bios or Asus Al Suite 3.

How should i go about doing it? A step by step guidance would be perfect.

Thanks!

 

[alexoiu]

Hi, You can try connecting it to a case fan header.

 

[Nonsensical86]

Hi, You can try connecting it to a case fan header.

All the case fan headers have been taken up.

 

[alexoiu]

Use a y splitter for 2 case fans, if the amperage allows it.

 

[Nonsensical86]

Another othrr options?

 

[dfk]

CPU_OPT mirrors the main CPU_FAN header, you cant control its RPM, so its best to use identical fans with similar RPM.

 

[alexoiu]

Another othrr options?

A fan controller able to handle 4 pin fans (pwm)

 

[Nonsensical86]

CPU_OPT mirrors the main CPU_FAN header, you cant control its RPM, so its best to use identical fans with similar RPM.

I bought the exact same fan that came with the hyper 212x which is the blade master. Same specification.

 

[Nonsensical86]

Or is it better if i switch the option fan to be connected to CPU_Fan and the pre-installed fan from 212x to CPU_opt?

 

[dfk]

Its the same even if you switch the fans. For this mobo, the CPU_OPT is going to mirror whatever RPM the CPU_FAN is at (it is BIOS controlled), so you will be controlling it indirectly with CPU_FAN via PWM.

If you really want to control it independently it would have to be on another fan header, CHA_1 for example, then you can control it via AI Suite3 using voltage (3pin fan). It's not really necessary as the BIOS/FanXpert will adjust the RPM of CPU_OPT according to cpu temps with PWM signals to/from CPU_FAN. This way it is more efficient at managing the pushed air depending on how fast CPU_FAN is spinning.

 

[Nonsensical86]

Its the same even if you switch the fans. For this mobo, the CPU_OPT is going to mirror whatever RPM the CPU_FAN is at (it is BIOS controlled), so you will be controlling it indirectly with CPU_FAN via PWM.

If you really want to control it independently it would have to be on another fan header, CHA_1 for example, then you can control it via AI Suite3 using voltage (3pin fan). It's not really necessary as the BIOS/FanXpert will adjust the RPM of CPU_OPT according to cpu temps with PWM signals to/from CPU_FAN. This way it is more efficient at managing the pushed air depending on how fast CPU_FAN is spinning.

But the CPU_OPT fan rpm is always lower than the CPU FAN. is it normal? For example, CPU FAN running at 700 rpm whereas CPU_ OPT fan only at 500 - 550 rpm.

 

[dfk]

Its the same even if you switch the fans. For this mobo, the CPU_OPT is going to mirror whatever RPM the CPU_FAN is at (it is BIOS controlled), so you will be controlling it indirectly with CPU_FAN via PWM.

If you really want to control it independently it would have to be on another fan header, CHA_1 for example, then you can control it via AI Suite3 using voltage (3pin fan). It's not really necessary as the BIOS/FanXpert will adjust the RPM of CPU_OPT according to cpu temps with PWM signals to/from CPU_FAN. This way it is more efficient at managing the pushed air depending on how fast CPU_FAN is spinning.

But the CPU_OPT fan rpm is always lower than the CPU FAN. is it normal? For example, CPU FAN running at 700 rpm whereas CPU_ OPT fan only at 500 - 550 rpm.

I suppose it's normal. To make it faster the main CPU_FAN has to be faster. As suggested here (similar lower RPM on opt header): http://www.tomshardware.com/answers/id-1770235/cpu-opt-fan-speed-low.html

You'll need to go into BIOS and disable Q-fan so it's not slaved to the CPU_FAN. Not all mobos allow decoupling of these two headers. Disabling Q-fan will make your fans run at full speed I guess, and allow other 3rd party software like Speedfan to control without BIOS interfering.