12x 3-pin fan controll via PWM or bios (push pull rads)

Abec777

Commendable
May 26, 2016
7
0
1,510
Hallo guys.I tested 2[strike] slipstreams[/strike] ultra kaze and ill be using 6 of them as a push-pull on my two 360 rads.So its 12 fans.But they are 3 pin fans
I want them to be cotnrolled from the CPU PWM so that they speed up only at high CPU temps to help cooling.
The power of course must be VIA PSU feeding the fans for obvious reasons.

q1)Is there a 3-pin split like the PWM akasa makes that can feed power from psu but use the 3rd cable to controll from motherboard?

q2)Im reading online that some motherboard support in bios to actually set all fans connected to mb folow the CPU fan.
Since im changing CPU mobo to either 1150/1151 do we have any knowledge on the subject?

General question:Any ideas on how this could happen?CPU temp controlled MANY 3pin fans.




 
Solution
There is a way to do this. I know of only one fan hub that can do it. It is the Phanteks PWM Hub. It is a fan Hub that MUST have a PWM signal from a genuine 4-pin fan header to work, and pretty much any mobo's CPU_FAN header does that these days. This particular Hub is unique - not like other 4-pin fan hub systems. This one uses the PWM signal to create its own set of six 3-pin fan headers each operating in Voltage Control Mode, which is what is necessary for control of 3-pin fans as you have. Like other hubs it gets its power from the PSU directly, via a connection to a SATA power output from the PSU.

HOWEVER, you are proposing to use fans with MUCH higher power consumption than most. The Scythe Ultra Kaze 120mm fan uses 0.60A at 12...
I don't know which model you will buy, just check it out what Amp it has. Keep in mind the motherboard fan_header will only output 1Amp or 12W, if you overload it and you will kill the MB. Like this one, it has 0.53A, if you add two you will kill the MB. If you will buy this one, you can use no more than 8, for some headroom, because it has 0.1Amp.

Also you can't control the 3-pin fan by PWM. If you want to control the 3pin fan speed either by voltage ( if the MB can do it) or the fan controller. Check the link for the 3-pin and 4-pin diagram, you will know why, because the #4 pin is for the PWM. http://cdn.overclock.net/c/c7/900x900px-LL-c7824258_3pinand4pindiagrams.jpeg
 

Paperdoc

Polypheme
Ambassador
There is a way to do this. I know of only one fan hub that can do it. It is the Phanteks PWM Hub. It is a fan Hub that MUST have a PWM signal from a genuine 4-pin fan header to work, and pretty much any mobo's CPU_FAN header does that these days. This particular Hub is unique - not like other 4-pin fan hub systems. This one uses the PWM signal to create its own set of six 3-pin fan headers each operating in Voltage Control Mode, which is what is necessary for control of 3-pin fans as you have. Like other hubs it gets its power from the PSU directly, via a connection to a SATA power output from the PSU.

HOWEVER, you are proposing to use fans with MUCH higher power consumption than most. The Scythe Ultra Kaze 120mm fan uses 0.60A at 12 VDC, or 7.2 W. That's 3 to 4 times a "normal" fan. Now the Phanteks PWM Hub says it can power up to 30 W total for all fans connected to it. If you insist on using those fans, one such Hub can handle 4 of them. But if that's your plan, there still is a way. Just be aware that your plan is to use nearly 7.2 A (~86 W) of power from the 12 VDC output of your PSU for fans alone!

If you really want to do this, you will need three of those Phanteks PWM Hubs, a 4-pin fan splitter with 3 outputs like this:

http://www.newegg.com/Product/Product.aspx?Item=N82E16812423163&cm_re=4-pin_fan_splitter-_-12-423-163-_-Product

and a PSU that can handle this fan load in addition to whatever else you're doing.

Normally one should never use a fan splitter with 3 outputs because a mobo header can only power up to 2 regular fans (not the heavy-duty ones you plan). BUT in this case the splitter will NOT be providing any power to any fan. It will be used solely to feed the PWM signal from one CPU_FAN header to three Phanteks PWM Hubs so each of them can use that signal to control its own headers.

For each Phanteks Hub you connect its female fan connector on a wire to one arm of the splitter, thus giving each its PWM signal. Then you connect each Hub's power connector to a SATA power output from the PSU. Recognize here that, in addition to consuming a lot of PSU power, you will be using up three of its SATA power output connectors. Finally, on each Hub you can plug in FOUR of your 3-pin Scythe Ultra Kaze 120mm fans, thus getting control of all 12.

Every one of those 12 fans will send a speed signal back toward the mobo on Pin #3 of its connector. But at each Phanteks Hub, ONLY the fan signal from the White Port #1 is actually sent on to the mobo, and the rest are ignored. THEN of the three fan speed signals going from the Hubs to the splitter, only ONE of them actually will be sent back to the mobo header. All this is because the header's speed measurement functions can only handle the speed pulse signal from ONE fan, so the splitter and Hubs all are designed to send back only one.
 
Solution

Abec777

Commendable
May 26, 2016
7
0
1,510



Dear god you are super nice.

Thank you very much.
Ill post results soon 6 fan temps vs 12 fan temps.