Question Asus Rog B450 Strix I Gaming need to connect x2 CHA_FANS

[tomachas]

Hi,

As the titles says I will have x2 CHA_FANS. As far as I know there are x3 4-pin conectors.

1 For the CPU
2 For the AIO_PUMP
3 For the CHA_FAN

I assume I would have to use 2 (pump) conector since I won't use it for the purpose right?

If so what would be the way to control 2 conector fan speed ?

Last but not least how to control 3 conector fan speed?

Thansk

 

[Barty1884]

Not completely sure, but the Pump header likely won't have PWM control - as pumps (typically) just need to run 100%.

PErsonally, I'd connect my CPU cooler to CPU_Fan, and then run a 2way fan splitter for the Chassis fans from the single CHA_Fan header.
You can grab a two pack of adapters for <$7.
https://www.amazon.com/Cable-Matter...ywords=fan+splitter+pwm&qid=1578934711&sr=8-7

Just an FYI, there will be no independent control over the two fans though. Because they're from the same header, they'll run at the same speed.

 

[tomachas]

Not completely sure, but the Pump header likely won't have PWM control - as pumps (typically) just need to run 100%.

PErsonally, I'd connect my CPU cooler to CPU_Fan, and then run a 2way fan splitter for the Chassis fans from the single CHA_Fan header.
You can grab a two pack of adapters for <$7.
https://www.amazon.com/Cable-Matter...ywords=fan+splitter+pwm&qid=1578934711&sr=8-7

Just an FYI, there will be no independent control over the two fans though. Because they're from the same header, they'll run at the same speed.

I've read somewhere that BIOS pump header mode can be changed but it didn't state clearly how to do so.

Somewhere else mods where undervolting pump header in BIOS to control fan speed. (Quiet nice idea if works)

Thanks for suggestion. I have bought Y splitter anyway just incase.

Want really to explore pump header hack though

 

[Barty1884]

On some boards, it can. On others, it cannot (via PWM).
That leaves DC control only... which isn't as granular.

Unless you'll have a need for 2x fans to be running at different speeds, the splitter will work just fine.

 

[tomachas]

On some boards, it can. On others, it cannot (via PWM).
That leaves DC control only... which isn't as granular.

Unless you'll have a need for 2x fans to be running at different speeds, the splitter will work just fine.

I don't mind doing DC control as long as it gives me a few incremental options to control voltage. I am sorted then. Ideally, I would have two separate controls over fans.
In my understanding AIO header should have PWM capabilities since it is 4-pin. In other words don't need PWM/4-Pin to run DC .