Q> Regarding 2 pin fans

[House of Alex]

Hi guys,

 

I got three case fans and only realize they have 2 pin connectors when they arrive. I have tested them on my fan controller individually but my system do not boot with all 3 fans connected.

 

I tried connecting the fans AFTER i boot into windows and that works, anyone got any idea why this is so?

 

Thanks in advanced!

[NotTristan]

So if you are talking about what I think you are talking about, old two fin pans were kind of individual to specific motherboards? (all though I could be totally wrong and I'm just making myself look stupid) so when your computer tries to boot it doesn't recognize them and basically says "nop, them some high volt things attached to my fan nipples" and doesn't boot to protect myself. but if you plug them in it doesn't really care. as far as I know they just run at max speed and are usually pretty loud and obnoxious; however I could be totally wrong.

[House of Alex]

Hey thanks for the reply i think you are right. 

 

It looks  something like a short circuit when i try to boot with all 3 fans on. Do you know of anyway to overcome this problem? Im sure the voltage from the fans are fine.

[WoodenMarker]

1 hour ago, House of Alex said:

Hey thanks for the reply i think you are right. 

It looks  something like a short circuit when i try to boot with all 3 fans on. Do you know of anyway to overcome this problem? Im sure the voltage from the fans are fine.

What motherboard and fans are you using? Which headers are you using?

You need to quote a post or tag a member when replying or else they won't get a notification that you replied to them.

[SuperCloneRanger]

I'm sorry to say @NotTristan but your wrong, but also not stupid, you had a go and you don't know what you don't know. both fans and fan headers are backwards compatible with each other no matter how many pins each have. you just loose functionality. if all you have is 2 pins the mobo will feed the fan a constant 12v. if you have the third pin the mobo can monitor the fan rpm and modify the speed by reducing the voltage. and finally the fourth pin adds pulse width modulation(PWM) which gives the mobo a more granular control of the fan speed by very quickly tuning the fan on and off. learn more here. https://en.wikipedia.org/wiki/Computer_fan_control#Pulse-width_modulation

@House of Alex I believe the problem your having may be due to over current protection,  dc motors (which is what computer fans are) pull a higher current than there operating current when they initially start, the 3 fans starting at the same time will cause a high current spike possibly causing over current protection. but to be certain i will need a little more info, 

motherboard make/model?

fan controller make/model?

is the fan controller powered by a Fan header of does it have molex or sata power connector?

what is the current rating of the fans?

will be marked on sticker of fan or box like 0.75A or 750mA

[NotTristan]

I know that it would pull a constant 12V, I just thought they were kind of special I guess *shrug* Thanks for letting me know though. And I didn't think about over current protection. this guy seems to know more about this than I do soooo, He'll teach you