PDA

View Full Version : CPU FAN! SIMPLE newbie QUESTION!! please help!


Noodles
10-03-07, 01:19 AM
My cpu fan, came with a 4 pin to MOBO. not a 4 pin to power supply cable...

it also has another 3-pin, for jumpers


it will get enough power to run it from the mobo? thats all it needs?

just seems bizzare that the other fans need to connect to MOBO and to PS.. and the main fan only to mobo


i have the cooler master eclipse

Noodles
10-03-07, 01:22 AM
just looked at the stock intel quad core fan... all it has is the 4-pin to mobo.. i guess thats it huh?

LORD-eX-Bu
10-03-07, 02:01 AM
plug both in. It will be enough. The three pin isn't for jumpers, it goes to one of the fan headers on your mobo. Look at the diagram in your mainboard manual, it should identify the location of all the fan headers that you need.

BCKator
10-03-07, 02:24 AM
I don't have that on my MB but isnt the 4 pin for PWM fan speed control? I would think you should use the 4 pin if you MB has that else use the 3 pin. For example
http://www.frozencpu.com/products/6096/fan-317/Scythe_Kama_120mm_PWM_Fan_DFS122512L-PWM.html?tl=g36c15s60#blank

Noodles
10-03-07, 02:59 AM
I don't know WHY i said jumpers... lol

But I guess for lack of a better word.

The 3 pin is for PWM Fan control yes... i said jumpers, because well its similar to that effect. To set it to High or Medium.

the 4 pin goes to MOBO.

and the three pin goes to NOTHIGN, its only for fan control



Just seemed a little odd to me that small case fans need direct to power supply and the main cpu fan doesnt.

I guess the mobo arranges the power properly

thanks for your help, all

jeffmd
10-03-07, 03:11 AM
You dont need a 4th pin for fan control, fans can be controlled via 3 pin as well. Its just that some mobos use 4 pin..some still use 3. The majority of cpu fans support either connections, but you don't need BOTH. A few fans that may draw more power then a mobo header can handle might have a 3 pin/2 wire connector so you can read its RPMs, even though it actually isn't powered by the motherboard. Such a fan would be doing some insane RPMs, or maybe powering alot of LED lights with it.