I recently bought two new fans for my desktop. (Rocketfish Gaming 120mm Fans) And Im new to this, but im assuming that 400-500 RPM is low as the CPU fan is running at 1500+. I believe the problem may lie in the fact that I plugged the fan (4pin) into a 3pin because I had no other 4pin slots. Is there a way to add more 4pin slots without buying a new mobo, or does the problem lie elsewhere?!?
Hello Compaker,
You can connect a 4-pin fan to a 3-pin header, but you will need to make sure that the end with the red wire is connected on pin 1 (should be labled as 1 on the motherboard). When you connect a 4-pin fan to a 3-pin header, it will always be on at full speed with no fan control option. This is what the 4th pin is for.
The link below can help show you more details on this.
Desktop Boards - 3-Pin and 4-Pin fan connectors
Hope this helps,
Shawn
thanks for replying, but the connecter on the fan has two little notches, and the motherboards 3-pin has a plastic piece that fits between those notches. The only way to connect the fan is to line it up in those notches, where i had it originally. The red wire is not on the end, it is on the 2nd connector. Is it possible that the speeds im getting are what the fan was designed for?
Probably not, usually lowest rpm on fans based on what i've seen is around 800 and that's low.
Here's a better wire diagram that should help more.
Motherboard (CPU) 3 Pin Fan Connector Connector Pinout - AllPinouts
That fan is only rated for 44 cfm airflow, so it is a pretty low speed fan.
hope this helps tell if I have it setup right
Last edited by Brink; 14 Jul 2010 at 00:36. Reason: attached video
In other news.... If you have a capable motherboard & fan, the motherboad's 4 pin header can vary the speed of a fan with a 3-pin connector.... https://www.sevenforums.com/overclock...tml#post809371
Just FYI as I know that's not what your problem was/is :)
Compaker,
It appears that you have it connected properly and all. It's just that it's only a 44 CFM fan running at most 1200 RPM with 23.5dBA, so it will not run very fast or loud.
http://www.rocketfishproducts.com/pr...RF-120FAN.html
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