Modding a 10Gbit/s 19" network switch to shut the thing up (silence mod)

[BigFatTeddy]

So. Disclaimer. This is not for the weak at heart nor for the hesitant. We will do some soldering. We will do metalwork. We will disassemble a network switch. We will face a unshielded power supply (and won't die). Don't do nothing I'm describing in this post.

 

Everything is done at your own risk. If you die, it's your own fault. Linus warns everybody all the time that power supplies can kill you.

 

With that said, let's carry on.

 

The objective of all of this is to get a fast network switch, ideally a 10GBASE-T with a bunch of SFP+ ports that is QUIET. And I mean, really quiet. This will for sure work for high-density network switches with 50+ POE ports, since we will replace those shitty 40mm fans with some larger fans.

 

~~~ Why fans in network switch are difficult ~~~

Let's do a little excursion on fans in switches. As you might have tried in the past (especially when reading this), replacing a fan in a managed 19" network switch is... complicated. If the manufacturer is using standard connectors (2, 3 or 4 pin fan connector, commonly referred to as a Molex KK connector, sometimes also called a TX3 connector), you can already feel lucky.

 

Now you just have to figure out the pin out... and find out that switch fans are of a very different breed than their PC cousins. No PWM, no tacho, the third pin is used for... something else. Most of the time it is something called a "dead fan detection" signal, generated from a hall sensor or some other dark magic. Whatever it is, the manufacturer of the switch will decide how it works and they won't tell you. Even if you ask. So if you're trying to use the fan headers on the switch mainboard, you will most likely end up with a fan alert in your switch when you swap out the factory supplied horrible little thingies.

 

But even if you're okay with that, you will now learn that fans used in network switch have a much lower start voltage than their PC counterparts. Actually most PC fans have very defined operating parameters (that's why people have invented PWM, to have a proper way of controlling the fan speed) and expect to be operated at 12V. You CAN somewhat operate them at lower voltages (Noctua is actually supplying resistors to lower the voltage) but nevertheless, they are expected to be operated at specific voltages. Some of them start at 7V, some of them start at 10V. Fans in network switches start at 3-4V and the firmware expects them to behave like that. So your new silent 40mm fans might not even start turning. Or will shut down after the initial power up thing. Noiseblocker-fans are known to work well, but... they only exist in 10mm width and really don't transport a lot of air.

 

You might be very happy with a slow turning 40mm fan in your 24port 1000GBase-T switch, no POE and all that. Because there is no power consumption in there. But if you're using a high-density switch with 48+ ports and POE, there will be heat in that switch. And quite a lot of it. If you're going for 10Gbit/s, you WILL need air movement. Those things get toasty. So? No 40mm fans.

 

So, what to do?

 

Easy, we just dump the entire concept of network fans, drill some holes, take 12V from the main power supply and operate silent 12V fans on top of the switch.

 

Oh. You will void your warranty with that.

 

The switch I chose to do that with is a D-Link DXS-1210-12TC (Revision A1). Which is not new and can be had on Ebay in Europe for around 500€ if you're lucky. Most people get rid of them because they're quite loud. I like D-Link, because their user interface is not totally shitty, I don't have to fiddle around with the CLI and it does what it's supposed to do. If you're a Cisco guy, kudos, but I don't care.

 

The first step is to open up the switch. I will not provide details for that, if you need a recipe on how to open the switch... you should not be doing this and should stop reading here.

 

When we have the switch open in front of us, we will see that the power supply is providing an ample amount of power and all on 12V. We will steal some of that. Disconnect the plug from the power supply and the mainboard. This is rather straight forward with this model (thanks D-Link for using cables with plugs!) but don't touch coils or anything in the open power supply. Don't do this! Any of this! You will die. Don't touch wires. Ever.

 

Okay, with the disconnected cable, cut a red and a black wire and solder another wire in between. I put a molex connector on the end of that wire, because I plan to use an adapter that I can disconnect if I want to open the switch again. It should look like this:

 

 

Second step is: Drill some holes through the top cover. For the larger holes (air has to go through the top cover), I use hole punches. These are rather expensive but create nice clean holes. However: hole time. Without the holes, no continue. So, put holes in there.

 

 

We then mount the fans on the top of the switch cover. This will cost us another unit in 19" measures, but if you want to do this (which you don't because you'll die and lose your warranty), just plan accordingly for the cabinet. Most of the time you might have clearance in the top slot to put some hacky stuff like this in there.

 

 

Last step is creating the adaptor for connecting the outside fan connectors to the power supply within the switch. Basic soldering, watch out for polarity. If you don't know what this means, stop here. I'm using those molex connectors a lot, so I have crimp tools for creating my own wires but you can also salvage connectors from your spare modular power supply box. You know, the cables you keep to use "as spares" but never do because power supply manufacturers change pinout or whatever. Now you have a nice outside-inside connection, on the outside I'm just using the cables provided within the Noctua-boxes.

 

 

Now you just have to assemble the cover back on the switch. Which is tricky with the SFP connectors. There are some trick on how to get this done, but all of them are just variants of fiddeling around. Maybe get a second switch and practice this before trying this with your new super-main-switch.

 

 

If you get there, now you have a frankensteined-19"-silenced down switch. I guess I have also a video demonstrating the noise-level of this mod.

 

 

 

The Noctua NF-A8 ULN is rated by the manufacturer for 34,8m³/h, the Y.S.TECH FD124020EB is rated for 17,9m³/h. Three Noctuas, so basically three times the volume moving through that switch with very little noise. And a nice push-pull config, like on those fancy Geforce coolers. Not sure if that does something, but I like it. Thing is fine for my basement without creating too much rage from my wife.

[Agall]

I feel like you could've just fan swapped the included ones with the same sized Noctuas or used those fan headers to add large intake+exhaust fans instead.

[BigFatTeddy]

Just now, Agall said:

I feel like you could've just fan swapped the included ones with the same sized Noctuas or used those fan headers to add large intake+exhaust fans instead.

But you actually read the post? Or let me rephrase that: I guess your feeling is not accurate.

 

As a hint: Noctua A4 will not even start in the D-Link switch because of the high starting voltage of the Noctuas. And: They're for sure not silent. No 40mm switch pushing 20 m³/h will be silent.

[mariushm]

Yeah... this is stupid ... you made it a 2U+ switch more or less (because there needs to be a couple inches above the fans as well) ... and a high risk to get something in the fan blades.

 

also the idea of the fans on the side is to get the air move from left to right or from right to left, between the fins of the heatsinks... your fans are placed in the worst places but I guess if you push enough air, it has to come out the sides eventually so you get it cool.

 

The noctua fans are pretty bad at static pressure, basically they're case fans, not radiator fans, they're not designed to push air through fins, the smallest obstructions will reduce the air flow.... your noctuas have 1.05 mm / 0.041 in H2o static pressure , the 40 mm fans have 9mm/0.36 in H2o pressure ... so the 40mm fans can push or pull a lot more air through the holes in the sides of the switch and through the fins.

 

As an idea, you could have purchase 2-3 of these and place them strategically inside the switch to push air through the fins of the heatsinks :

 

ODB600-12LB Orion Fans | Fans, Blowers, Thermal Management | DigiKey

 

 

 

 

 

 

FD124020EB datasheet.pdf

[Agall]

34 minutes ago, BigFatTeddy said:

But you actually read the post? Or let me rephrase that: I guess your feeling is not accurate.

 

As a hint: Noctua A4 will not even start in the D-Link switch because of the high starting voltage of the Noctuas. And: They're for sure not silent. No 40mm switch pushing 20 m³/h will be silent.

Then why not fan swap with your 12V soldering mod to push+pull the smaller fans?

[BigFatTeddy]

  

18 minutes ago, mariushm said:

Yeah... this is stupid ... you made it a 2U+ switch more or less (because there needs to be a couple inches above the fans as well) ... and a high risk to get something in the fan blades.

 

also the idea of the fans on the side is to get the air move from left to right or from right to left, between the fins of the heatsinks... your fans are placed in the worst places but I guess if you push enough air, it has to come out the sides eventually so you get it cool.

 

The noctua fans are pretty bad at static pressure, basically they're case fans, not radiator fans, they're not designed to push air through fins, the smallest obstructions will reduce the air flow.... your noctuas have 1.05 mm / 0.041 in H2o static pressure , the 40 mm fans have 9mm/0.36 in H2o pressure ... so the 40mm fans can push or pull a lot more air through the holes in the sides of the switch and through the fins.

 

As an idea, you could have purchase 2-3 of these and place them strategically inside the switch to push air through the fins of the heatsinks :

 

ODB600-12LB Orion Fans | Fans, Blowers, Thermal Management | DigiKey

 

 

 

 

 

 

FD124020EB datasheet.pdf 58.02 kB · 0 downloads

 

Obviously I'd disagree, simply because there is no room inside the box for the fans you linked. This wasn't the first try on silencing a switch and I don't know if you ever tried to use one of the fans you linked, but those fans are definitely not silent. Not at all. There would be zero improvement on noise level, basically just adding the need to have top openings without any benefit.

 

I have installed the Noctuas in a push-pull configuration, the center one is pulling the air from the chassis. This works quite nicely and has lowered the temperature on the SFP+ chipsets by approx 5-6° degrees compared to the stock fans in the switch. The other temperature sensors show same temperature as with the stock fans. But at a much lower noise level.

 

I agree, adding the fans on top will require additional considerations when using the switch (for me, this is not of any importance, since this specific switch is mounted upside down on the bottom of a shelf, not in a cabinet - but I have done this with other switches to just shut them up and especially with POE-switches, this adds a lot of comfort in office environments when providing ethernet to an entire floor).

Edited April 2 by BigFatTeddy
Quote...

[BigFatTeddy]

2 minutes ago, Agall said:

Then why not fan swap with your 12V soldering mod to push+pull the smaller fans?

Noise? The 40mm fans are just way louder. I have done this with other switch for installations in OT-environments, especially when operating in edgy conditions so additional cooling was needed, but in those environments noise is of no matter. There it's just about moving air through filters so nothing gets in the switch.

 

But this switch is for my "home environment" and reducing noise is the main objective.

[Alex Atkin UK]

On 4/2/2024 at 10:38 PM, BigFatTeddy said:

Noise? The 40mm fans are just way louder. I have done this with other switch for installations in OT-environments, especially when operating in edgy conditions so additional cooling was needed, but in those environments noise is of no matter. There it's just about moving air through filters so nothing gets in the switch.

 

But this switch is for my "home environment" and reducing noise is the main objective.

Surely for this to be effective the fans should have been placed directly above each heatsink?  It seems like the cooling is going to be very uneven and would perhaps have made more sense to use much bigger fans.

 

Plus why use a push/pull combination?  Wouldn't it make more sense to be all push as it will force the air more consistently across everything inside, reducing the chance of hot spots?

[BigFatTeddy]

9 minutes ago, Alex Atkin UK said:

Surely for this to be effective the fans should have been placed directly above each heatsink?  It seems like the cooling is going to be very uneven and would perhaps have made more sense to use much bigger fans.

 

Plus why use a push/pull combination?  Wouldn't it make more sense to be all push as it will force the air more consistently across everything inside, reducing the chance of hot spots?

The much bigger fans didn't happen because the largest hole punch I own is 75,2mm diameter, and since those things are rather expensive, that was the size of the hole and that was the size of the fan.

 

The thing with the hotspots is something to be considered, true, but to be fair, the entire thing is designed to have constant airflow with just 2 40mm fans, and the heat production with the chipsets is not a peak-one but a more continuous one.

 

The reason for the push/pull config was simply because after various experiments with other switches and other configs, the three fans in that config work best, especially for this particular model with the stupid additional chipset in the upper left corner of the board for the additional 2 combo-ports. This chipset is... not good.

 

The larger aluminium heat sink at the bottom is doing the least amount of work and I actually do have a model of the switch with only two heat sinks, so that one can mostly be ignored. The placement of the fans is chosen to get some decent airflow to the power supply and to that specific chipset in the top left.

 

It's not like the push/pull makes an awful lot of difference, switching them all to a push-config will just add 2° C to the black heat sink.

[dogwitch]

On 4/5/2024 at 3:41 AM, BigFatTeddy said:

The much bigger fans didn't happen because the largest hole punch I own is 75,2mm diameter, and since those things are rather expensive, that was the size of the hole and that was the size of the fan.

 

The thing with the hotspots is something to be considered, true, but to be fair, the entire thing is designed to have constant airflow with just 2 40mm fans, and the heat production with the chipsets is not a peak-one but a more continuous one.

 

The reason for the push/pull config was simply because after various experiments with other switches and other configs, the three fans in that config work best, especially for this particular model with the stupid additional chipset in the upper left corner of the board for the additional 2 combo-ports. This chipset is... not good.

 

The larger aluminium heat sink at the bottom is doing the least amount of work and I actually do have a model of the switch with only two heat sinks, so that one can mostly be ignored. The placement of the fans is chosen to get some decent airflow to the power supply and to that specific chipset in the top left.

 

It's not like the push/pull makes an awful lot of difference, switching them all to a push-config will just add 2° C to the black heat sink.

yeah.

i notice on my mobo m.2 slot 1  gets almost no air flow with a big gpu dumping heat and.... like wth did design not catch this...

the chipset vrm blocks any air coming  in front of the m.2 slot...

anyhow how i fix going forward is stick on heat set(metal fins)

1950x asrock mobo