Who doesn't hate their fan controller?
Alright....one thing I really wanted to grab by the horns in this build was fannage. I wanted to keep it quiet with 16 120mm fans, but not get dinky 800RPM fans...no easy task!
I've always had rheobus fan controllers, which are nice, but have a few problems:
1) No 'settings.' i.e., you never really know what voltage your fan is doing unless you have a DMM hooked up, there's no semi-arbitrary 1-2-3-4-5-6-7-8-9-10-11 numbering either :( Just a knob that turns...
2) LEDs suck.
3) Finite loads. i.e., you can't hook up two high powered fans on one circuit without overloading it
4) Droop. 11.3ish volts when you want 12? Yucky-ucky.
Since around May I've wanted to build my own fan controller...a switch-based fan controller with 0V, 5V, 7V, 8.7V, and 12V settings. A switch-based fan controller would not have ANY of the aforementioned weaknesses....and with 4 different running settings, it would also have enough variability. I thought the idea was perfect :)
I knew it wouldn't be easy, considering I'd have two different feed voltages (12V and 5V rails), with four different 'ground' poles (ground, 3.3V, 5V, and open). About a month later into the planning, I realized I needed two :(
Then about another month later, I realized I'm not so great at DIY, and I still had almost zero luck finding the ultra-complicated switch I needed. I moved on trying to find pre-made switch based controller.
Unfortunately, all the switch based ones I found switched between a closed (normal) 12V circuit and a circuit with some resistance via a resistor/transistor pair. This still had a finite (and SMALL) load, damn LEDs, and droop on higher loads. And only two settings still :(
So I was stumped for awhile....
Then I found the Zalman ZM-MFC1.
http://img250.imageshack.us/img250/3...rontpremq2.jpg
http://img295.imageshack.us/img295/9...backprext5.jpg
It has two hard-wired 12V/5V/open switches (great) and four rheobus channels that are fairly weak (meh). It's also butt ugly with the graphics, LEDs and clear plastic. It's rheobus does have one GREAT advantage over the Sunbeam's: the minimum setting is ~5V....so it does actually have two distinct settings, as well as a variable middle-ground :)
And on further inspection I noticed something slightly bothersome: the 12V/5V/open switch doesn't have a 3-pin connector....instead needing bare wires. Not too difficult to cut and strip a wire, but I'd rather not.
Fortunately, some quick thinking has lead me to a few solutions to most of the problems :)
1) Switch connection is fixed!
Performance-PCs sells great sleeved wirings, and after a bit of digging their website, this fan adapter became something of import to my plan: http://www.performance-pcs.com/catal...oducts_id=3596
So in addition to my two Zalman MFC1s, I bought four of those :)
And ta-da! Stripped off the connector on the 2-pin side and they work well ;) Highly recommended!
http://img293.imageshack.us/img293/5...ckwiredzf3.jpg
2) The ugliness is fixed!
Unfortunately no retailer has a fix for this: the fan controller is butt ugly.
Fortunately, I have a fix ;)
You shake your hand for a couple minutes, white stuff comes out, let it dry, and you have a white fan controller :D
BTW, I was talking about white spray paint, perv.
So I bought some of that Krylon Fusion spray paint for plastic....
took off these pieces (from each controller):
http://img250.imageshack.us/img250/6...npiecesrh1.jpg
sanded off the ugly arrows and words on the front of the controller, and had my way with them with the Fusion paint...
I must say I liked the results :)
http://img187.imageshack.us/img187/3...ontpostvx1.jpg
I even did the back of the plates :D
http://img171.imageshack.us/img171/1...ackpostit9.jpg
2.5) Requisite PCB shots!
Something I learned when getting into computers....when you have a PCB of any sort, you take pictures of it and post it :p:
Front:
http://img184.imageshack.us/img184/1...rontpcbbu4.jpg
Back:
http://img169.imageshack.us/img169/9...backpcbhy7.jpg
(of note is that although Zalman says only the blue-socketed headers can do RPM sensing, all the circuits are identical, just the wires they include are different...cheap company)
3) Those damn LEDs....hmmmm, LEDs look good when OFF!!!
I was originally going to pull the LEDs (again, I hate LEDs....my monitor has 2.3Million pixels, I don't need 4 more on the front of my computer, thank you), but the way they're installed would have made that difficult....and I found no good filler for the plastic panel, so that was off. Then I considered just leaving them....but they FLICKER when you undervolt the fans! So in a move of desperation, I shorted one out while I was running a fan....and it worked! The LED went off, the fan kept going on :D Now all 8 LEDs on the rheobus are shorted....haven't tried the 4 on the switches, I'm fearing they're hard wired, we'll see.
Next post: the wheels on the bus go round and round? Oh wait, those are fans....a lot of them!