Y splitter question

[Vibora]

Hey, I don't have enough chassis fans connectors on my motherboard and I have a y splitter with one 4pin and two 3 pin connections, do the 3 pin act as a regular 4 pin? I'm just confused if they would operate the same.

 

[Biohazard777]

4 minutes ago, Vibora said:

Hey, I don't have enough chassis fans connectors on my motherboard and I have a y splitter with one 4pin and two 3 pin connections, do the 3 pin act as a regular 4 pin? I'm just confused if they would operate the same.

 

Out of the original 4 pins, one wire is sense/tach

It reports back to the mobo / fan controller how fast the fan is actually spinning.
You do not want more than one fan sending that signal back, otherwise the reported speed would be wrong.

All fans will operate the same, only 1 (connected to 4 pin) will report back speed (as it should be done).

[Vibora]

11 minutes ago, Biohazard777 said:

Out of the original 4 pins, one wire is sense/tach

It reports back to the mobo / fan controller how fast the fan is actually spinning.
You do not want more than one fan sending that signal back, otherwise the reported speed would be wrong.

All fans will operate the same, only 1 (connected to 4 pin) will report back speed (as it should be done).

I see, so what are my options if I want all of them that are connected to report? Is there a y splitter with a few 4pin connections?

[Biohazard777]

2 minutes ago, Vibora said:

I see, so what are my options if I want all of them that are connected to report? Is there a y splitter with a few 4pin connections?

As I've said:
"You do not want more than one fan sending that signal back, otherwise the reported speed would be wrong."

[Vibora]

10 minutes ago, Biohazard777 said:

As I've said:
"You do not want more than one fan sending that signal back, otherwise the reported speed would be wrong."

I'll clarify my question

What are my options so that I can make all of them report back and act as a pwm fan? Is it even possible if I don't have enough connectors? I obviously want all to operate with the needed RPM 

[Biohazard777]

5 minutes ago, Vibora said:

What are my options so that I can make all of them report back and act as a pwm fan? Is it even possible if I don't have enough connectors? I obviously want all to operate with the needed RPM 

They will work as PWM fans.

All fans will receive PWM signal, only one should report back speed.

The only "downside" is that they will all work at the same RPM.

To clarify, say you have 3 fans (F1 F2 F3).
You connect F1 to the Y splitter connector 4 pin, and you connect F2 and F3 to 3 pin connectors on that Y splitter.
F1 is reporting back speed, the other two are not (nor should they).
Say your mobo /  fan controller wants the F1 to spin at half speed, it will set the duty cycle to 50% for F1,
that same PWM signal will be shared with F2 and F3, F2 and F3 will spin at 50% as well.

 

If you want F1 to spin at 50%, F2 at 100% and F3 at 70%,
then you can't do that with a dumb Y splitter,
you'd need a fan controller (or use different headers on your mobo, one for each fan).

[Vibora]

Just now, Biohazard777 said:

They will work as PWM fans.

All fans will receive PWM signal, only one should report back speed.

The only "downside" is that they will all work at the same RPM.

To clarify, say you have 3 fans (F1 F2 F3).
You connect F1 to the Y splitter connector 4 pin, and you connect F2 and F3 to 3 pin connectors on that Y splitter.
F1 is reporting back speed, the other two are not (nor should they).
Say your mobo /  fan controller wants the F1 to spin at half speed, it will set the duty cycle to 50% for F1,
that same PWM signal will be shared with F2 and F3, F2 and F3 will spin at 50% as well.

 

If you want F1 to spin at 50%, F2 at 100% and F3 at 70%,
then you can't do that with a dumb Y splitter,
you'd need a fan controller (or use different headers on your mobo, one for each fan).

Oh ok I see thanks for clarifying, but do usually fans on the same side (top front bottom) are spinning on a pretty close rpm range? I guess it's not of a big deal if everyone spin the same?

[Biohazard777]

1 minute ago, Vibora said:

Oh ok I see thanks for clarifying, but do usually fans on the same side (top front bottom) are spinning on a pretty close rpm range? I guess it's not of a big deal if everyone spin the same?

You are welcome.
Yeah it is common practice to have all of the fans on one side of your PC (or even all case fans) to spin at the same speed.
As long as that speed can be adjusted, and it can since all the fans will share the same PWM signal.