swiftech 8 Way PWM Splitter. Anyone who has used this?

[bracka]

Yesterday I discovered an issue which I was not anticipating. Maybe anyone else has experience/suggestions.

 

Idea was to use Swiftech 8 way pwm splitter to control 6 Corsair SP120 QE PWM fans and use 'speedfan' as control utility.

Link to splitter: http://www.swiftech.com/8-WayPWMsplitter.aspx link to fans: http://www.corsair.com/en-us/air-series-sp120-pwm-quiet-edition-high-static-pressure-fan

However a strange issue occurred where once you connected more then 4 fans all control from speedfan was lost and fans started to run at full speed. As if the 5th fan shorted the circuit and removed any kind of control.

 

CPU fan connector was used on Gigabyte x58a-ud3r. Connector was switched to PWM mode in BIOS instead of Auto.

Using only 4 fans the splitter worked flawlessly and it didn't matter which connectors on the board were used. The amount of fans seemed to "break it".

Has anyone else encountered a similar problem?

[topsu]

What is amperage on each fan?

 

I would not recommend going over 1A total from one header.

 

And your fans aren't even PWM, you should try using case fan header which is usually voltage controlled.

[ameel]

Do not despair!

Had similar issue running a pump and 6x SP120s on the 8-way splitter.

I built a PWM amplifier by following the schematic posted by bing on overclockers.com, here:

Schematic from bing posted here: http://www.overclockers.com/forums/showthread.php?t=700653

Parts needed:
556 Timer
4k7 resistor
100 upf capacitor

I've also hotglued the bottom of my board to avoid any risk of shorting.

My pc is now DEAD QUIET!!! (awesome SP120s)

Here are some pics:
Top


Bottom (pre-hotglue)


Bottom (post-hotglue)


All Connected


Original Schematic (by bing)


No-clutter design

[VSG]

Yesterday I discovered an issue which I was not anticipating. Maybe anyone else has experience/suggestions.

 

Idea was to use Swiftech 8 way pwm splitter to control 6 Corsair SP120 QE PWM fans and use 'speedfan' as control utility.

Link to splitter: http://www.swiftech.com/8-WayPWMsplitter.aspx link to fans: http://www.corsair.com/en-us/air-series-sp120-pwm-quiet-edition-high-static-pressure-fan

However a strange issue occurred where once you connected more then 4 fans all control from speedfan was lost and fans started to run at full speed. As if the 5th fan shorted the circuit and removed any kind of control.

 

CPU fan connector was used on Gigabyte x58a-ud3r. Connector was switched to PWM mode in BIOS instead of Auto.

Using only 4 fans the splitter worked flawlessly and it didn't matter which connectors on the board were used. The amount of fans seemed to "break it".

Has anyone else encountered a similar problem?

 

Welcome to the weird world of proprietary PWM. This happens only with Corsair PWM fans so far because they don't follow the Intel PWM standards and would rather you use Corsair Link to control them.

[ameel]

Welcome to the weird world of proprietary PWM. This happens only with Corsair PWM fans so far because they don't follow the Intel PWM standards and would rather you use Corsair Link to control them.

Swiftech customer support team reported:

 

Corsair's fans require a much stronger PWM signal than other PWM fans. So far Corsair's are the only ones that we can confirm require such a strong PWM signal. Due to this if you load 5 or more fans off of a single motherboard fan header, the fans will run at full speed. Our splitter was not designed with any signal boosting capabilities, so there really isn't a way around this.

 

 

If you build a PWM amplifier/booster (like I did above), it fixes the problem. I'm currently running 6 Corsair SP120 and a WC pump on the swiftech 8-way pwm, and can control the speed perfectly.

[VSG]

Yes, that does help. But realistically how many people do you think will do that? I am running 6 SP120 PWMs per channel (2 channels total) on my controller as well without issues but most will be stuck with 4 or less.