Case Fan Power?

[Thor]

I am getting ready to buil me a new server.. I have a Antec case and am going to put 2 80mm case fans in the case. What is the best way the power these fans? Off the motherbaord or with the 4 pin milex connector? my motherboard does have 2 extra fan plugs.. Would this be too of a drain on the motherboard here is the specs of the fan I am wanting to use

Sunon 80mm by 25mm with a 3 pin motherboard connector.

Specs:
- 12v
- 0.18 amp
- 2.1 watts
- 2900 rpm
- 39 cfm
- 32 decibels


Thanks

 

[NewCompGeek]

i would use the 4pin Molex

 

[Crucial]

<< i would use the 4pin Molex >>



Thats nice. Would you care to tell us why?

I run all my case fans(all 2 of them) and the hsf from the motherboard headers and they work fine. Don't bother with the molex connector. It will be easier to route the cables and it will look nicer.

 

[Olias]

You could put them on a 25 ohm, 5w variable resistor pot and dial in what ever speed you want. The inductive load of the fan you mentioned would be P/I^2 (2.1/0.18^2) or 65 ohms. With the 2 fans in parallel you would get half the resistance or 32.5 ohms. This would vary the 2 fan speeds from 6.8~12 volts. The fans should handle down to at least 7 volts.

 

[bozo1]

All depends on the specific fan and your motherboard. Usually, any fan that draws more than 3-watts runs the risk of blowing the header on the motherboard. However, some newer boards will support up to 5 watts. I'd check your motherboard manual or website to be sure but with that fan sucking 2.1 watts, I wouldn't worry about it.

 

[Thor]

Well I have checked the 3 pin power plugs on my motherboard will support 350mA 4.2 Watts and since the fans only take 2.1 watts
I think I will be OK to use the 3 pin plugs and I will be able to use the cool rpm monitor.. got to keep my new server COOL....