Splitting PWM 4pin Fan Connector

[UaVaj]

http://www.ebay.com/itm/280553936724

how much amperage/wattage can a typical motherboard PWM 4pin fan connector deliver? in other words how many 140mm fan can one safely run off a single the PWM 4pin without frying the motherboard.

MB in question is ASRock Z77 Extreme4. looking to run three 140mm PWM fan for CPU cooling.

 

[DesiPower]

The motherboard manual should tell you the amperage or something related, following formula might help you determine whatever information that might be lacking...
Watts=Volts X Amps

iirc, generally fan use less than 1 amp, typically around .5 not more than .7 or .8 max..

 

[Eureka]

Most (but don't quote me, so verify it within your manual) modern headers should be good to up to 1A on each header. Each 140mm fan should be around .2-.5A, depending on how fast the fan can spin and how big the blades are.

 

[Rvenger]

I wouldn't do more than 2 fans on 1 fan header. Asrock does not provide specs but I can tell you that I can safely run 2x 140mm fans no problem.

 

[BrightCandle]

I have seen motherboards go up as higher as 4A, but 1A is much more typical.

If you are going to start grouping fans together you might want to consider a fan controller which will often put out 5A or more per channel. I do this on my water cooling fans (10 of them in all!) so I can group them by radiator and control them together.

 

[Vectronic]

I have seen motherboards go up as higher as 4A, but 1A is much more typical.

I tried finding the limits before for Z77 Ext4... since that's how I killed my last board (shorted Cha Fan1 directly, not overloaded)... didn't. So just stick with the 1Amp assumption, it will at least provide/be fine with that.

If I get the time, and decide which PSU I might want to kill, I'll test it with my old board since it still spits out power to the fans. All I really know is that the board doesn't provide any sort of safety/fuse of any kind... normally a board will have resistors in case they are overloaded, burn out the resistor... nope... it'll keep trying to output until it fries a PCB trace.

Going by this, it seems the PCB Trace *could* handle about 2.5A at least to Cha Fan 1... but... yeah.

 

[UaVaj]

thanks for the help.

for the same $$.
http://www.newegg.com/Product/Produc...82E16812119248
direct power from the psu via molex.

could only imagine the increase current draw from a dusty 140mm fan.
safe than sorry.

also no manual fan controller. prefer pwm control. one less thing to worry about.