Add fan to WRT3200ACM

Hi !

I've got WRT3200ACM and with actual wheater, it goes up to 90 degrees (I'm not really sure about the 3 temperatures: what each one corresponds to ?)

ssh router sensors                                                                                                                                
Adapter: mv64xxx_i2c adapter
temp1:        +59.7°C  
temp2:        +62.2°C  

Adapter: Virtual device
temp1:        +92.3°C  

So, I'd like to add a fan to cool my router.
I've seen a couple months before a post on openwrt where a guy added a fan, but as the forum had a problem, there's not search avalaible, and some posts are missing.

The usb port is busy but the eSATA (according to some images, it could be a eSATAp, no?) port is not and there is an eSATA to 3/4 pin adapter cable like the Noctua NA-SAC5. With a fan like the StarTech FAN7X10TX3, it could be a solution.

Do you think my is it possible ? Does the eSATA port can delivery enought power ? Do you have any other silent fan to recommand ? Or any other fan mod ?

Thank you !

All fans are going to be noisy.

If there is space you could experiment with a larger heatsink or replacing the aluminium heatsink with a copper heatsink or more efficient heatsink design.

Wall mounting may also be worth experimenting with.

A larger fan with it own power supply placed underneath the router would be quieter and provide better cooling than a small internal fan.

Thanks for your reply.

Changing the heatskin is not an option for me, to much work and I don't have the skill to do that.

Place it on the wall neither (WAF...)

A big fan under the router, why not, but I can't find a one that with it's own power supply. And I had no intention to put it inside, just put in on with double-sided adhesive or something like this.

But I've found this: a modular USB fan. I just have to find a eSATA to usb cable...

Why that? Doesn't this device have a USB/eSATA combo-port?

In my experience, there are very few fans that move air that are quiet enough for home-office use.

For a quiet, small fan, that might fit in the case itself, the Noctua A4x20 would be my first choice, with the thinner A4x10 if you didn't have room. The larger Noctua fans are reasonably quiet as well, and many come with a "quiet-mode" adapter (likely nothing more than a resistor to drop the voltage). The "PWM" versions allow direct control of the speed through a separate line that potentially could be driven off a "spare" GPIO pin and a little circuitry to drive what I believe to be a 5-V logic level. (I haven't built my own PWM-fan driver yet.)\specs\rev1_2_public.pdf

The 120-mm Yate-Loon D12SL-12 are another old favorite of mine, but I don't know if they're still available and aren't PWM.

If you do install in the case itself, be aware that the turbulent flow over any vents you have or add may cause more noise than just the fan itself. Big openings are better than a lot of small ones in this regard.

I'd run off the 12-V supply, rather than the USB supply, no matter where you install a fan, especially if you intend to connect USB devices. The regulated 5-V rail may only be able to supply 1 A or some other limited amount of current.

Check out products on Amazon by AC Infinity. I bought their dual 120mm fan set and they are silent on low speed.

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You could use a USB phone charger to power the fan

@tmomas: you're are f*****g right !! I've tried with a USB key, perfect. I didn't know that it could be possible. One less problem :slight_smile: thank you

@jeff: wow, what a detailed post. I know about the Noctua's fan, they are silent but not cheap. And as posted before, I unfortunately don't have the skill and the time to open the case, dismantle and weld a fan. That would be perfect but maybe later... I'm mostly afraid to take a wrong small noisy fan.
By the way, are there "spare" GPIO available on the router ?
For the voltage, I found a guy that plugged the fan directly on the 12V (I think) rather than the USB. As I said, maybe later...

@dlakelan: nice fan, but on amazon, it's a bit too expensive (~40€ for France), but they have a power modulator

@mbo2o: I hadn't thought about it. But I prefer to try with a eSATA/USB fan before

I found a cheaper one than the AC Infinity, for less than 15€. With Noctua NA-SAV2 to fix them to the grid, what do you think ? Does the eSATA port deliver enought power ?

I did a quick check and the Yate-Loon D12-SL12, 120 mm fan is available on Amazon US for US$11, a significantly less than the Noctua 120 mm fan at US$20. The Yate-Loon starts reliably at 7 V (across a "standard" PC's 12-V and 5-V lines) and runs very quietly.

Silent PC Review, RIP, used to be a great source of information on fans and more. Somewhat dated now since it hasn't been updated in a couple years:

I don't have a WRT3200ACM, so can't comment on availability of GPIO pins. The little 40 mm fans can be screamers so there is a lot of value in slowing them down when higher levels of cooling are required. The best of the 120 mm fans are pretty quiet and I typically use a "set-and-forget" approach to selecting a speed.

For my modem and a router (c2600), im using some old 20cm fans that i have from my old pc case. I just used some screws underneath to make them able to suck air. Then i took an old 6v phone charger and built a simple power supply with triple 3 pin output.

Finally i put my devices on top of the fan. Its a very simple mod.

5-6v are enough and should make any 12cm fan or bigger quiet. You can probably built an usb powered interface. Should only need some safety feature to not kill your usb on the router in case of malfunction. Thats why i took an external psu.

With that i was able to save 20 °c, and make my vdsl2 modem fully stable. It was kinda unstable before and produced a lot of disconnects, than training (can take up to 3min for vdsl2) once the cpu hit the 65°c. Probably the device had an hotspot building up without cooling.

Wouldn’t you use something like the fan in the WRT1900AC v1? It sounds fine at 50% speed. Bit of a screamer at 100%.

I think that device would also give the most clues about GPIO, although they are different.

Yeah, that's a lot. Here in the US that twin fan thing is $20 which is like 17 Euro, a lot less than the French price. And the single version of that fan is only $13

@jeff: thanks for the feedback. I agree for the 40mm vs bigger. I've order a AIO 120mm fan with USB. I'll see what it's worth.

@BIGFAT: I'm also a fan of simple mod :slight_smile: My USB port is busy, but the eSATA not. I hope I can cool him down as much as yours !

@lantis1008: I don't which one they use as I don't have the 1900AC. And I don't have the skill to plug it as they do. Maybe later with some time and research...

@dlakelan: lucky you in the US :wink:

I finally order the ELUTENG 120mm with USB and power modulator. With rubber stick, I'll see what it worth.
I'll keep you in touch if someone is interested !
Thanks all for your advices

Well thats my modem thats run cooler, i didnt look for the temps on my c2600.

Just a quick feedback: I've just received my Elutang 120mm plugged in the eSATA port and just installed on the router ("à l'arrache" in french) and here are the results:

ssh root@router sensors
Adapter: mv64xxx_i2c adapter
temp1:        +39.0°C
temp2:        +40.9°C

Adapter: Virtual device
temp1:        +66.1°C

More than 20 degrees won ! The fan is silent, even at it maximum. Very happy with my purchase :slight_smile:

I just have to add the rubber feet to perfect the installation.

If anyone has some questions, I'd be happy re reply.

Thanks all for your replies and your suggestions !


If this is still appropriate, see my mod

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This is what I use on Openwrt router wrt1900acs v2, at an ambient temperature of 28 degrees the router together with the nf-a4x20-pwm fan manages to have 47 degrees without a fan reaches 64-65 degrees.