Is there any way to do this?

Ideally I'm looking for some sort of adapter that does the following:

4 pin PWM signal ---> Adapter (turns high/low PWM signal into high/low voltage --> 3 pin case fan.

Problem is as follows.

I have a rather unusual (and amazing) 180mm sealed water cooling unit (like Corsairs H60/H80 but 180mm instead of 120mm). The radiator actually performs better than the new H100.

Right now I have a push/pull system set up with two 180mm fans. I have been unable to find any 4pin PWM controlled 180mm fans. At full blast they are a little loud (in a quiet room) so I'd like to control them so they wind down when the CPU is cooler.

Fan controllers are typically unreliable, as you have to stick a temperature probe somewhere, and you are not getting actual core temp.

Because of this I wanted to use the PWM signal off of my CPU header on the motherboard, and use smart monitor mode to control the fans. I even got a three way PWM splitter that appears to work well, but only seems to work with PWM fans.

I am only really interested in controlling the fan speed. Don't care too much (at all) about the ability to read RPM values. A dumb, rheostat like voltage controller would be ideal.

Much obliged,
Matt

I found something called the Nanoxia PWXM but it appears out of stock/discontinued everywhere

Actually, here's one that is still sold.

But it has to be shipped from the UK

Here. This is what you are looking for:

http://www.performance-pcs.com/catalog/ ... s_id=30056

Since you have a MSI motherboard, have you checked the bios to see if it could allow "Voltage" control for the cpu header ? My MSI allows to choose between PWM and voltage mode

I heard that some motherboards have this option, but I couldn't find it anywhere in my BIOS

Thank you for the suggestion though!



Excellent! Thank you, something like this is exactly what I have been looking for.

I probably won't be using the rheostat portion of them (I don't even have empty expansion slits in which to put two of these), but I guess I can just set them to PWM mode and hide them somewhere inside the case. To bad I am paying for the rheo portion when I don't need it :p

For more information about what these are being used for, see here.

Pretty impressive stuff, i might get one for my TJ08-E frontal fan and just have the mobo control it. Investigating a little more i stumble on this video, Sunbeam Twister 120 CPU Cooler & Rheosmart 6 Fan Controller Video Review, he shows the pci style, but they also have 3 fan n 6 fan controllers with switches to go manually or pwm, pretty nice stuff.

Yep, this 990FX bios is a real step back regarding fans ! (vs 890FX MSI's bios for exemple)
http://www.msi.com/product/mb/990FXA-GD ... div=Manual



Maybe a bios update will improve the situation ?

Maybe.

Part of the 990FXA-GD80's issues I think stem from the complete rewrite of the BIOS to be UEFI. (why they did it so it still looks like a traditional bios but with a mouse I'll never understand).

I wound up ordering the 6 fan control version.

I only really needed two or three PWM fan controls, and was going to get the 3 fan version, but it turns out that once I added the 3.5" to 5.25" adapter bracket (my case doesn't have any external 3.5" slots) it was cheaper to just get the 5.25" 6 fan version :p