4 pins Fans and fan direction

Astralv

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I have 2 questions:

1) My Asus z87 Deluxe motherboard supports Fan Experts. This comes in form of software that let user define location of fans and type of operation. It supposed to detect temperature and adjust speed of the fan. The motherboard has 4 pins connectors. I was told that 4th wire is to send information back to Fan about rotation speed. I need to by 4 more fans, and I do not see any fans with 4 pins. When it says 3 and 4 pins connection, it usually means 3 pin small connector and 4 pins Molex connector. Have you seen Fan with 4 pin small connectors for motherboard?

2). I had to disassemble the 88 mm exhaust fan on the back of computer case and now I can not tell which way to connect it, as both sides have Aerocool logo. How do I tell which direction fan blows? I feel air from both sides. Thank you.
 
G

Guest

Guest
You want to look for PWM fans. To tell direction of airflow, there is an arrow on the bezel of the fan that indicates which direction it flows. Typically, the front of the fan is the side the blade hub is on but it depends on the positioning of the blades that determines airflow. Look for the arrow, it is usually somewhere on the frame or bezel of the fan.
 

Astralv

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Thank you for the info. How will it help me to know which direction it turning? I would still not know where air go more...

What you mean by "the front of the fan is the side the blade hub is on "? What is Blade Hub?
 
G

Guest

Guest
The arrow means "The Air Goes ---> THAT WAY" and the blade hub is the part of the fan that has all the fan blades on it if you were to remove it from the plastic frame.

Normal airflow on a case is Front = Intake, Rear = Exhaust. So the fans on the front would be blowing INTO the case where the fans on the back (minus the power supply fan) would be blowing air OUT of the case.
 

Astralv

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So lets say I found front of the fan, because wires closer on that side or it looks better. Lets say the arrow clockwise. (Did not see it but assuming). Do I puut front of the fan toward the mash (facing outside) or facing inside of the case to make it exhaust? Thank you.
 
G

Guest

Guest
IMG_556dd4244.jpg


 

Astralv

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ah-hah! Tanks, I will look for it- have to get inside the case as I connected it by my best guess.

I spoke with Aerocool (my case maker's) tech support person and he says, "Why do you want fans to be controlled? Let them run on full speed. It will not save much energy, and you do not want fans to slow down and let your motherboard or CPU get hot and then hope fans will speed up on time. (They sell lots of fans but no PWM fans, and fans that came with the case (2) were 3 pins). It kind of makes sense. Besides, my motherboard only has 4 fan connectors. I want more fans because my CPU runs over 50C, and because I like lights. PWM fans do not have leds. Do I want to have 4 pins fans and control speed or let them run from Power supply via Molex, save money and get colors? Thank you.
 

Astralv

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Few- yes, may be 1 or 2. On Newegg they all out of stock. On amazon- no leds. http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=BitFenix+Spectre+PWM+#/ref=sr_pg_1?rh=i%3Aaps%2Ck%3APWM+case+fan&keywords=PWM+case+fan&ie=UTF8&qid=1371602636

I have space for 6 fans. Front fan is 3 pins, so it will not be controlled any way. Also... It shows different speed in BIOS and in AI Suit (software with Fan Expert). It, for example, shows my back fan 1200 rpm in BIOS while only 300-400 rpm for the same fan in AI Suit, and it is 88 mm fan. So if it can not detect right speed- how can I rely on it to control 4 fans? Also I will still have to connect front fan to PSU via Molex because it is 3 pins, and free ports on motherboard for PWMs.