Dahua NVR Quiet Silent Fan Mod

Kinchyle

Young grasshopper
Aug 10, 2017
40
16
I have a Dahua NVR but I'm sure this would work with anything.

Noctua 5v fan (runs at about 15db at 100%)

Noctua A-Series Cooling Fan Blades with AAO Frame, SSO2 Bearing (NF-A4X10-FLX 5V)

3-pin reducer cable to get the fan running at 60% (even quieter and less than whisper)
Universal 3-pin CPU Speed Reducer PVC Cable Cord Lead for Electric PC Laptop Fan

Black twist tie (you pick the length)
Verdental Versatile Metal Cable Ties Home Kitchen Cable Ties - Food Bag Sealing Cable - Cable Cord - Recyclables Sturdy Plastic Garden Plant Twist Tie Strap Cutter (Black)

2 sets of Copper heatsink (10mm X 10mm x 14mm) It comes with 10 per pack
Enzotech MOS-C10 Forged Copper MOSFET Heatsinks

Instructions:
Put on the heatsinks
The heatsink come with thermal tape. I chose tape so it wasn't permanent. I also didn't want to mess with the stock heatsink and try to find a copper replacement...
Stick all the heatsinks on top of the stock heatsink. I put them next to each other and filled up the core. I did leave room around the edges but the stock heatsink got a lot cooler to the touch after the heatsinks so figured it was better than stock. I didn't bother with laser gun and couldn't find system or reporting access for thermal output to know changes.

Hook up the fan
Remove the whinny stock fan.... Connect the reducer cable then connect it to the 5v Noctua fan. You'll need to connect the reducer pin on the board using the right 2 holes (it has 3...). You can google or I believe the left over holes on the cable will be facing the back of the appliance.

Strap the fan down
Unplug the fan to be safe. Use the garden twist tie to pull out a good bit of the cable. Use the holes in the fan and the screw edges on the board and tighten the fan down where it sits flat on top of the copper heatsinks. I thought about trying to prop it up so it blows sideways and has better backflow but this seemed more sturdy and it did the job (good flow and quiet!).

I wish I could get thermal readouts because I think it could run safely as fanless with those large copper heatsinks and the case being vented with the air slots. If anyone has this running for awhile fanless let me know or knows the upper heat ratings and I might play with the laser heat gun to see how it works out.
You can't even hear the NVR with it sitting 5 feet next to you but if I did it again I might try one of the 100mm or larger Noctua 12v fan (it would run slower rpm at 5v). The fan would still need to be 10mm height. The 40mm has a good bit of room around it sitting on top of the heatsinks. The current design runs and sounds great(quiet) so I'm not going to mess with it...
 

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Noctua 5v fan (runs at about 15db at 100%)

The top of the Dahua NVR5216-4KS2 case isn't really cut out to support smooth airflow through the little fan. I tried the 40mm Noctua 5v fan in place of the stock fan, but it was still far too loud for my preference (with and without the case top off). For now I have the case top off and an old Silverstone 120mm fan blowing across the top of the board, which is nearly silent. Eventually I plan to transplant the internals to a mini-ITX case (SilverStone Technology Co., Ltd.- SG05-
 
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Larger fans are the way to go if you can get them to fit because they run slower rpm(less whine) than smaller fans. Did you try a speed reducer cable? I found the noctua(which is a known quiet fan company) to be loud also at 100%. At 60 or less it was alot quieter and seemed to have reasonable air flow to cool the large heatsink.

Agreed on not ideal to have the tight fit but at the low speed and not needing alot of air to do the job it seemed like a good balance. I'll borrow a laser heat gun and do some heat comparison.
 
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Did you try a speed reducer cable? I found the noctua(which is a known quiet fan company) to be loud also at 100%. At 60 or less it was alot quieter and seemed to have reasonable air flow to cool the large heatsink.

A reducer cable would be a lot less work (and cheaper) than transplanting to a different case.
 
I've used one of these on 12v fans with a lot of success to tune noise to air flow.
Zalman Fan Speed Controller FANMATE-2

I tried it on 5V and couldn't seem to get it working. It looked like it would require tweaking the wires which I didn't want to fool around with.
If you had a 12v fan it should work to connect to this then to the 5v board. I hear the trick with 12v though is if you slow it down too much and connected to 5V it doesn't have enough juice to get it turning initially...

It's also larger than a reducer cable. I was prepared to just do another reducer cable to get 60% of 60% :) but it seemed quiet enough.
You have me curious though to try a larger fan and go even quieter, maybe even fanless with those large copper heatsinks.

When overclocking or dealing with cooling I usually go over upper specs of the processor with heat and not just "blow air at it".
If I know it can run at 80 but it's the max I just get it running at 70 at peak...

I can't seem to find processor utilization or heat registers. I doubt Dahua is Linux either to just tap in to the OS.
I'll give another go, and use a laser gun. I have 3 cameras which have the IVS so I'm assuming motion processing is done at the camera??
How do you make an NVR sweat anyways to see if I can keep it cool while it's at a load?
Make sure all the cameras are recording at the same time (i.e. general 24/7 recording)?? Then have the interface up with all cameras??

I usually run prime algorithms on the processor then run 3d graphic benchmarks at the same time then see when the heat of the cpu plateaus and stays within safe numbers (and the device doesn't shutdown or get white dots all over the screen...). Not sure how I can do similar testing with NVR to know fanless is working...
 
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I've used one of these on 12v fans with a lot of success to tune noise to air flow.
...
Hi @Kinchyle -
I tried a single SilverStone Technology PWM Fan RPM Reduction Cable, and it got a 40 mm Noctua 5v A-Series Cooling Fan down to the same noise level as the Western Digital drive.
Next I cut a hole in the case top to get better airflow to the fan, which was then covered with a filter to keep cat hair out. (safety notice - don't try cutting metal without clamps and a drill press)
To dampen the fan and drive nose, I added acoustic foam to the inside, replaced the feet with Sorbothane discs, and also adhered Sorbothane sheets to the outside of the top and bottom of the case.
The NVR is now mounted to a vertical surface and quiet enough ;-)
 

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Nice modifications, gentlemen. I am going to link this thread in the cliff notes.
 
12V of course


Sent from my iPhone using Tapatalk Pro
 
Did you install any of the included resistor cables?

The fan may have a minimum startup voltage of X VDC. If that is the case, then measure the voltage at the fan header when you turn on the system and see if it is at least X volts or higher.

From the FAQ on this fan:

Different starting voltage: Most network devices use voltage-based speed control. If the new fan has a higher starting voltage than the original fan, it may not start up right away. This may lead the device to display errors or even shut down because it suspects a fan failure.

Here is the FAQ link: NF-A4x20 FLX



Sent from my iPhone using Tapatalk Pro
 
Yeah, the Dahua NVR4108HS-8P-4KS2 is noisy and noisier than the previous one I had. It was same model. With ceiling fan and blues on the NVR does not bother me. Are all Dahua NVRs noisy?
 
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No i didnt install any resistor cables. Tested fan again and about 30sec it starts to spin itself. I measured connectors and it takes about that 30seconds to voltages raise to little above 12V. Thanks for your help Giomania!
 
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Yeah, the Dahua NVR4108HS-8P-4KS2 is noisy and noisier than the previous one I had. It was same model. With ceiling fan and blues on the NVR does not bother me. Are all Dahua NVRs noisy?
The NVRs that don't have built-in PoE are much quiter, as they use an external power brick doesn't have a fan.
 
I just thought I'd add a few comments.

First, I love getting computers and other gadgets as quiet as possible. We become accustomed to a lot of ambient racket from PCs and the like, and it's a blessed relief when we can get them all to be as quiet as possible.

Next, it's always best to keep our electronics as cool as possible. That doesn't mean we need howling fans, but good airflow is essential. So tradeoffs need to be made, for sure.

Larger slower-turning fans are always quieter than smaller high-RPM fans that move the same amount of air. So if possible, open things up and use slower, larger fans to do the same job.

Look at how old-school sirens are made. The concept is usually a spinning disk rotating very near a stationary disk, with holes drilled in both disks. Now think about a typical fan setup. Often, a fan is mounted very close to a cut-out in a case, or a "finger guard" that is stationary. That makes a siren! So mounting the fan farther away from the stationary grill or cut-out in a case can quiet things a LOT. You want to avoid building a siren when you design a fan system. It doesn't take too much space between the rotating blades and the stationary grill to quiet a fan system substantially! Just installing some spacers between a fan and the case can help a lot. But you then also need a shroud or other way to seal up the "connection" between the fan and the opening in the case so air won't "short circuit" inside of the case. You want to pull in ambient outside air, after all.

Keep your electronics cool with a lot of air flow. Don't starve your devices for air flow for the sake of quiet. But design your air-moving equipment carefully to get good air flow without making a lot of racket. For most semiconductors (and a lot of capacitors), their life is cut in half for every 10°C of increased temperature. Cool is good! But quiet is also good.
 
This post was really helpful for me so I wanted to add to it with what I did to my Dahua NVR to change it from a freight train to a whisper quite baby's fart without compromising heat extraction requirements.

As per Kinchyle suggestion I installed the heatsinks plus the Noctua fan. Instead of the 3 pin reducer Kinchyle suggested I used a Noctua NA-RC12 adaptor ultra low noise reducer (here) which takes the fan down to 3700 RPM. The reducer is a bit hard to find for sale on its own but it does come included with this fan from Noctua (link)

I then replaced the PSU fan with a Scythe Mini Kaze Ultra (Amazon link).

The Noctua will require using the little splice plugs so that you can go from 3pin to 2 pin. The Scythe also will likely require use of the splice plugs for the purpose of extending the cable.
 
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I have a Dahua 8 camera Power-Over-Ethernet NVR (NVR 4208-8P-4K-S2). I suffered from the same fan noise issue here as everyone else. To echo the comments and provide some clarifications and precautions, at least on this NVR unit.

A) This NVR has two fans. The first is commonly called the 'case' fan. It is for cooling the motherboard and NVR chips. The second is the 'power supply' fan.

B) The case fan was almost silent. It is a 40mm x 40mm x 10mm ("thin") fan operating at 12 volts that blows air out of the SIDE of the NVR case (left side as you face the unit). Mine was a Sunon MagLev HA40101V4-D26C-999 rated at DC12V and 0.8 watts. I didn't see any reason to replace this fan. (I chose to install the copper heat sinks described above by Kinchyle. After hours of operation with 7 fans running in a warm attic, the entire heat sink was cool to the touch. I suspect I could run this system fan-less. But regardless, the running fan was quiet enough that I didn't worry further about this aspect of the system.)

C) The power supply fan, on the other hand, would probably be sufficient to fly a small model airplanes. It is LOUD. This fan blows air out the BACK of the NVR case, immediately next to the power switch (because it is part of the power supply unit). This fan is a 40mm x 40mm x 20mm ("thick") fan operating at 12 volts. Specifically, mine was a EFB0412HHD, 12 volt, 0.15 amp by Delta Electronics connected by a 2-pin wire to a 12-volt supply. The fan is fully contained within the power supply unit. So if you take the top off your NVR, there will be a self-contained silver metal power supply box, and the fan is inside that box. The fan is rated at 30.5 dB. Which is LOUD. But it is also highly effective – see the PERFORMANCE DIFFERENCES at the end of this write-up.

So please note - there was some discussion about 5 volt fans, but both of mine are 12 volt. If you try a 5 volt fan on a 12 volt power supply, at best it will be VERY noisy until it quickly burns out. This is the opposite of what we are looking to accomplish.

My steps to address the Power Supply fan noise were:

1) Turn off the NVR and unplug it. Remove the top cover (screws along the back). Unplug the power supply from the circuit boards (two simple connectors), remove the screws holding in the power supply, and take the power supply unit out of the NVR.

2) Unscrew and remove the cover of the power supply unit.

3) Unscrew the two screws holding the current fan-of-doom at the rear of the power supply unit and wiggle the fan out.

4) Using a Dremel-like cutting tool, cut away the metal fence/screen that was covering the location of the fan. Air blowing over that fence/screen creates a lot of noise and reduces airflow, meaning the fan has to work harder or is less effective at a given speed. Use appropriate safety measures (gloves, glasses, clamp down the power supply when working on it, keep all shavings out of the power supply (I used a rag to cover the innards)). The Noctua fan has enough of a plastic protective cover that I didn't feel an additional metal fence/screen was necessary in my specific installation. The fan is blowing outward, so there is no need for a cover to protect dust/debris from going in to the hole where the fan is.

5) Install the replacement Noctua NF-A4x20 FLX fan. It is a 40mm x 40mm x 20mm fan at 12 volts. It draws 0.05 amps, while the stock fan was at 0.15 amps, so it will actually draw less power. It runs at 5,000 RPM at full power. Currently $15. But please be aware that it moves far less air under far less pressure than the stock fan. See PERFORMANCE DIFFERENCES at the end of this write-up.

6) You will need to connect the fan's 3-pin female connector to the existing 2-pin male connector on the power supply circuit board. You do this by cutting off the old 2-pin female connector from the old fan and splicing the wires to an accessory wiring adapter included with the Noctua fan, they call the "omnijoin." It is hard to describe in words, but VERY simple - black to black and red to red. The "omnijoin" even includes connectors for the wires, so you just cut, trim, and then use the included adapters to re-connect them.

7) OPTIONALLY - You can also purchase the Noctua NA-SRC10 3-pin low-noise adapter cable. Currently 3-pack for $8. This is simply a current reducer (resistor) that will reduce the 12v power to only 7v. Lower power means the fan turns even slower, reducing it from 5,000 RPM to 4,400 RPM (about a 12% speed reduction). It simply plus in between the omnijoin connector and the wire for the fan - this looks just like a stiff piece of wire, but reduces the current to the fan. But remember that reduced speed means reduced airflow means reduced cooling. (There is also an Ultra Low-Noise Adapter Cable, which reduces the fan speed to 3,700 RPM. For comparison, the fan is rated at 14.9 dB at 5,000 RPM, 12.2 dB at 4,400 RPM and 8.5 dB at 3,700 RPM. The Ultra Low-Noise Adapter is harder to find. The stock fan is 30.5 db!!!!!) I highly suggest assembling entirely WITHOUT the low-noise adapter cable and seeing if the level of sound is acceptable. Because the stock set-up moves far more air than the replacement fan, so if you further reduce the power of the replacement fan, its performance will be hurt even more. If not, then install the cable. See the data below for the performance differences.

8) Reassembly is the opposite of disassembly. Be careful with all the extra wiring you've now installed in the power supply - avoid getting it into the fan's movements, covering air vents, or pressing it up directly against things that look like they might heat up.

9) Optional considerations: The noise of the fan increases significantly due to resistance. That can be resistance to air moving out (which we've eliminated by cutting away that screen/fence). It can also be resistance to air moving in. Anything that covers vents means it has to work harder. But those also vents keep kitten paws & cat air, children's fingers and human hair from getting in to muck up the works. In general, as a point of reference, a window screen type material reduces airflow by 50%. So if you can place this somewhere that is hair, animal, debris and person free, one option is to open up the vents a bit more (Dremel tool to remove some of the dividers in the metal box. You want to do this as far away from the fan as possible (if you start opening up holes adjacent to a fan, the air just recirculates and doesn't cool the entire system. So some ideas might be to open up several air vents on the right side of the NVR (opposite side of the case fan) and some on the front of the power supply (opposite side of the power supply fan). In general, I'd thing that opening things up like this - if it can be done safely- will be better for the electronics than installing a "noise reducing" cable which simply runs the fan slower and allows the electronics to run hotter. This all comes down to your specific situation - inside an air conditioned home in Maine, or in a garage in Arizona will have totally different cooling needs.

PERFORMANCE DIFFERENCES

Comparing the Sunon MagLev HA40101V4-D26C-999 and the Noctua NF-A4x20 FLX...

They are the same size (40mm x 40mm x 20mm). They are both rated at 12 volts DC. The stock fan draws 0.15 amps while the replacement Noctua only draws 0.05 amps, so no problem there.

BUT -

The stock fan runs at 8,200 RPM creating 30.5 dB of noise. In doing so, it moves 15.78 cubic meters of air per hour and creates a pressure of 0.354 inches of water (creates a lot of pressure to move a lot of air, effectively removing heat from the electrical components).

The replacement Noctua fan runs at 5,000 RPM (or 4,400 or 3,700 depending upon the noise-reducing cable installed) and creates 14.9 dB of noise (or 12.2 dB or 8.5 dB depending upon the noise-reducing cable installed). At the full 5,000 RPM, it moves 9.4 cubic meters of air per hour and creates a pressure of 0.09 inches of water (creates far less pressure, moving less air, removing less heat). If you put the Low Noise Adapter or Ultra Low Noise Adapter on that Noctua fan, the numbers will be even lower.

Anything you can do to help improve airflow for the new fan will not only further reduce the noise it makes, but will also help make up for some of the difference in the performance between the two fans. But overall, there is no free lunch and the Noctua fans aren't a free lunch - you give up something in exchange. One option I haven't tried was simply to install the noise reducing cable into the stock fan - simply cutting down its 8,200 RPM by about 10%, and clearing away the screen from in front of the discharge, might have been enough. Which I had a dB meter.


Sources:

EFB0412HHD Delta Electronics | Fans, Thermal Management | DigiKey

Fans - Products
 
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>MF40201V2-1000U-AA99 says it moves 13.08 cubic meters per hour with 0.17 inches H2O pressure from 6,000 RPM producing 21 dBA of noise
>Stock fan moves 15.78 cubic meters per hour with 0.354 inches H2O pressure from 8,200 RPM producing 30.5 dBA of noise
>Noctua moves 9.4 cubic meters per hours with 0.09 inches H2O pressure from 5,000 RPM producing 14.9 dBA of noise.

So ya, looks like your Sunon MF40201V2-1000U-AA99 cuts the noise quite a bit (30.5 to 21 dBA) without losing nearly as much performance (15.78 vs 13.08 m3/h) as the Noctua fan (which only gets 9.4 m3/h)!

Overall, seems like there is a fairly direct relationship - for every X m3/h of cooling there is Y dBA created. Some may be a bit better than others on that ratio, but as long as we are dealing with 40mmx40mm fans, there is no magic solution. I suppose cutting some big holes and putting in a much larger fan (at lower RPM but moving more air with less noise) would be the ultimate solution.