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Jackietools

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Just bought an Antec 900 case. It comes with 4 fans and all are only molex connected with a 3 speed switch. I want them connected to my Asus mobo so it can control speed. I see molex adapters to 3 pin female connectors but only 2 wires run into the 3 pin female connector. Shoulnt there be 3 wires not just 2? If it is a 3 pin connector I assume it shoukd have 3 wires so fan speed can be monitored and adjusted. Does the mobo provide enough current to run fans . Do I need to buy new fans with connectors for 3 pin mobo headers? Thanks? This is my mobo Asus P8Z68-V LGA 1155 Intel Z68 HDMI SATA 6Gb/s USB 3.0 ATX Intel Motherboard

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you need fan with 4 wire to be pwm so the motherboard could control the speed,but for the 3 pins pins fan it show it's speed but always work full speed .the one you got work at the speed set on the switch and are not been control by the motherboard but by the switch settings,the molex is for power a live wire (red) 12 v and a ground wire (black).that means your motherboard wont control the speed

Jackietools

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Forgot to mention no adapters for fans are supplied with case. I would have to buy them
 

vertical777

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you can stick 2,3,4 pin fans into the 3,4 pin(male) of the motherboard the 2 pins are for the power V+ and V- the 3rd pin is for RPM monitoring and control of the mobo, the 4 pin ones are PWM controlled fans
 

vertical777

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if I understood you correctly, your fans have male molex connectors connecting into a female molex to female 3 pin(with only 2 pins, the power ones).
you can plug the 3pin into your motherboard and control the fan voltages via the BIOS, but without the 3rd pin you cannot monitor its RPM.
 

Jackietools

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No the fans comw with a male and female connector with 3 speed switch. I would have to by a connector that attaches to the molex of the fan at one end and is a 3 pin female at the other. I do see these adapters but like I said the female headers of the adapters only have 2 wires going into them which would defeat the purpose of the mobo controlling the fan speed correct? Can the mobo control the speed with only 2 wires attached? The mobo does have software for fan speed so maybe that controls the voltage thru the bios to adjust fan speed?
 

Jackietools

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Antec says just set the switch to high if you plan to connect direct to mobo but again will the mobo be able to control fan speed auto with only 2 wires going into the 3 pin female. Is this normal to just have two wires going into three pin adapter instead of three. When I look online all I see are adapters with 2 wires going into the 3 pin adapter
 

Jackietools

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http://www.shopwiki.com/3%7Epin-Fan-Male-to-4%7Epin-Molex-Male-Female-Adapter-Cable. this is what I think I need but do you see there are only 2 wires going into the female pin. Should there not be third wire and if so where can I find the adapter with the third wire
 

scout_03

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look at page 2.2 of the manual the number one description you got a spare cpu 4 pins connector then another 4 pins for chassis fan a 3 pin for chassis fan then 2 three pins for power,you could at least put two 4 pins fans on motherboard and you still have 3 spare connector for the 3 pins fans
 

Jackietools

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I understand I have the male connectors on the motherboard but the trouble is finding the correct molex to female fan connectors. As I stated all the 3 pin connectors I see only have 2 wires connected to them. Dont they need the third wire so fan speed can be controlled or is that the norm for a 3 pin connector to only have 2 wires connected. What happens with the third terminal on the connector if there are only 2 wires?
 

Jackietools

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Sorry but Im not following. My case has 4 fans. All four only have a male/female connector for power and a three position switch for speed. I want to connect them to my mobo so it can control their speed so I need a connector that will go from molex to 3 pin female. All the connectors I see will fit my fan at the molex end but the end that would then plug into the motherboard only has 2 wires going in. That means one terminal has no wire. Doesnt the mobo require all 3 wires to control speed. Will it work with just the 2 wires or will it only run at full speed?
 

scout_03

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you need fan with 4 wire to be pwm so the motherboard could control the speed,but for the 3 pins pins fan it show it's speed but always work full speed .the one you got work at the speed set on the switch and are not been control by the motherboard but by the switch settings,the molex is for power a live wire (red) 12 v and a ground wire (black).that means your motherboard wont control the speed
 
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