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ISO: 12V Fan Controller 4-pin molex for 3 fans?

Posted: Wed Apr 30, 2008 6:29 am
by SilentBen
The Zalman Fanmate 2 controller... is it possible to have that control all 3 of my 1200rpm Scythe Slipstreams?

I was thinking about all the fans not controlled by the motherboard, a seperate modular plug from the PSU and using a 4-pin [-O O O O-] molex fan controller for voltage regulation. (Not the mini 4-pin like seen on motherboards... the full size that plugs into older HDDs, CDROMs, etc.)

I don't think I want to do any voltmods, I think having an on-the-fly adjustable fan controller is better for my needs.

For example:
PSU -> Dedicated 12V modular plug -> Fan controller -> Fan 1 4-pin molex splitter -> Fan 2 4-pin molex splitter -> Fan 3 4-pin

Any recommendations?

Posted: Wed Apr 30, 2008 6:35 am
by jhhoffma
Well, the Fanmate2 is essentially a variable resistor so the the more current you put through it (i.e. the more fans) the hotter it will get. There's a little H/S inside the Fanmate2 that I've seen get warm with one fan, so I don't know that I'd run 3 120mm fans off one, regardless of where it's power is sourced from.

I'd buy a dedicated fan controller and run each fan independently. You can find some pretty cheap on Newegg and Directron.

Posted: Wed Apr 30, 2008 7:08 am
by SilentBen
Hmm. I thought about that idea too, but I didn't really want to have 3x wires and 3x fan controllers sitting around. A bit of clutter!

The current is rated at 0.26A per fan at 12VDC, so that would be 3.12W/fan. I believe you are correct then, since the FanMate 2 is rated at up to 6W power handling. 2 of these fans may push the limit!

I just noticed the fanmate isn't even the right 4-pin molex connector, it's the mini! I'd imagine it works the same, just the voltage goes across smaller gauge wires. I wonder how I would even connect all them on to one header?

The APEVIA FC-01 Multi Fan Speed Controller - Retail looks ok... 0.26A x 3 = 0.78A, the device states to handle 1.2A.

Any other suggestions?

Posted: Wed Apr 30, 2008 9:15 pm
by SilentBen
I got bored today... decided to try a safe voltmod!

I took apart a 4-pin molex splitter with a screwdriver to do the 5v mod... (removed yellow +12v wire and put red +5v wire in its place), and wired four of my five Scythe Slipstreams 1200rpm to it.

My result is each fan is running between about 750-800rpm! It kind of doesn't make sense, since 1200rpm @ 12v... I expected a fairly parallel relationship, where 5v would be around 500rpm.

The sound difference is AMAZING! I didn't even know my computer was on aside from the PWR_ON light!

My temperatures didn't even change... maybe a 1C more in the ambient case temp! Full load and gaming made no difference either.

I think I may make a 12v/5v as described in one of the stickies. That will save me from opening the case up on a hot day to give the extra CFMs! :D

As another thread posted... 800rpm slipstreams are the sweet spot. 1200rpms move A LOT of air though. My 2 cents, 1200rpm slips if you want to control them (voltmod or fan controller) and 800rpm slips if you don't. I haven't dropped mine to 500rpm yet, but I can't even hear mine at 800rpm!

Posted: Thu May 01, 2008 6:28 pm
by jhhoffma
Welcome to the wonderful world of undervolting!!! You're life will never be the same... :P