3 pin to 4 pin header and vice versa

[stevenly]

Title^      what happens?

[Billy_Mays]

For fans yes it would work

[EnergyEclipse]

6 minutes ago, stevenly said:

Title^      what happens?

Well, nothing. As nothing can be done. In the real world, it would not make sense for such to be applied as

[stevenly]

1 minute ago, EnergyEclipse said:

Well, nothing. As nothing can be done. In the real world, it would not make sense for such to be applied as

so the fans will just run at 100% if i plug em that way

 

[W-L]

6 minutes ago, stevenly said:

so the fans will just run at 100% if i plug em that way

 

If you run 4 pin fans on 3 pin headers it will be controllable but only in DC voltage control mode and not PWM capable, similarly with 3 pin fans on 4 pin headers as long as the mode is setup as DC voltage control. 

[PeterPorker3]

21 minutes ago, stevenly said:

Title^      what happens?

Basicly: if you plug a 4 pin fan into a 3 pin header or a 3 pin fan into a 4 pin header, the fan controler or motherboard can't control the fan speed as precisely, making the fan spin faster when it doesm't need to for example.

[LogicalDrm]

16 hours ago, stevenly said:

so the fans will just run at 100% if i plug em that way

 

Depends on mobo. If mobo supports DC control, having 3pin fan on PWM header still allows control. There's also the "bad advertising" factor as not all 4pin mobo headers are PWM. And not all fan headers even on modern boards are controllable at all.