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Started by AdStan | | 4 answers
Molex PWM splitting - what 3pin/4pin speed variations from one header?
Right, I need some help confirming two things,

I know 3pin fans can be Voltage controlled and 4pin are PWM controlled. And I know that I can add a molex splitter to my MB header to increase my connections like in the link below, but....

http://

1. I have a CPU header for my CPU used, but only one chassis fan header (ITX MB). But I have 2 case fans and want to install 2 extra external fans.....(HTPC is in a closed TV unit so is overheating....so I want to put a fan drawing cool air from underneath the TV unit and one exhaust fan removing air out the back). IF i connect a x4 molex PWM splitter to the chassis fan header and connect the 4 fans (2x 3pin + 2x 4pin), will the motherboard utility work (ASROCK FAN-tastic tuning) and control them all as if they were one fan?

2. IF yes, I assume the 4pin fans will be RPM controlled but will the 3pin fans just spin at 100%?


PS - I am just building the PC at the minute and dont have all parts so cant test completely just yet, I just dont want to order the 2 extra 4pin fans and splitter if this is not going to work well!

Corsair 250D
ASROCK B86M-ITX
Intel i5-4460
Arctic Freezer 13 (it fits easy in this case althought specs say 95mm max!!)

Thanks for any help or suggestions!!
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Best solution chosen by AdStan

October 6, 2014 12:34:04 AM

Yes, you will sort out power issue and controlling rpm not an issue.
October 3, 2014 8:10:06 AM

Thanks for the suggestion but I will be limited for space and I was trying not to add much more cost.

Plus if I get the splitter that connects to the MB with only the RPM and PWM lines and only draws its power from the molex does that get around ur worries of drawing 4 fans worth of power from the header?

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