MP 1,1-5,1 Mac Pro (4.1/5.1) aftermarket fans WITH automatic SMC control

[iModFrenzy]

@crackajacka77 The most difficult thing is finding appropriate 3-pin fans with the proper fan speeds. They:

• must be able to spin slowly enough for the SMC to properly control them (see minimal speeds below). Otherwise they stop rotating completely.
• must be able to spin fast enough to sufficiently cool the Mac (depends on the fan model and ambient temperature, workload, hardware).

PSU, Intake and Exhaust​

• PSU: 120x25mm, Intake & Exhaust: 120x35mm but can be replaced with 120x25mm
  • PSU: minimal SMC speed: 600 rpm (500 rpm possible via iStat)
  • Intake: minimal SMC speed: 600 rpm
  • Exhaust: minimal SMC speed: 600 rpm (500 rpm possible via iStat)
• Confirmed working models:
  • Noctua NF-S12B redux-1200 (500-1200 rpm) [case / airflow optimized fan]
  • Noctua NF-P12 redux-1300 (550-1300 rpm) [pressure optimized fan]
  • Noctua NF-A12x25 ULN (xxx-1200 rpm) [newest technology, most quiet, great allrounder]

PCI/Expansion​

• 92x35mm but can be replaced with 92x25mm
  • minimal SMC speed: 800 rpm
• Confirmed working models:
  • Noctua NF-B9 redux-1600 (800-1700 rpm)
  • Noctua NF-A9 FLX (800-1600 rpm)

CPU/Booster(s)​

• Single tray: 1x 80x25mm
  • minimal SMC speed: 856 rpm (714 rpm possible via 3rd party like iStat)
  • Working but might be too slow for high load: Noctua NF-R8 redux-1800 (856-1800 rpm)
• Dual tray: 2x 60x25mm
  • minimal SMC speed: 1112 rpm (928 rpm possible via iStat, 800 rpm via Macs Fan Control)
  • Hard to find a replacement, as the original ones have a huge range of speed (up to 5200 rpm)
    • not working (stalling): Noctua NF-A6x25 FLX (xxx-3000 rpm)
    • unconfirmed possible candidates: Noiseblocker NB-BlackSilent Pro 60mm PR-2 (xxx-2500 rpm) or PR-1 (xxx-1800 rpm)

I additionally recommend removing the fan guards (Intake, Exhaust & PCI) for even quieter and better cooling thanks to the reduced air resistance.

GPU fan pinout for connecting 4-pin PWM fans is illustrated in Post_#358 by @Minimum91

Edit: Updated image. Credit to all who posted the original images/pinout infos!
Tag me with other confirmed fans I should add above.
View attachment 2160866

appreciate this, so if I want to do without fan control(setting a minimum rpm), my best route would be piggybacking off the Mac Pro’s 12v(4th wire?) with a resistor to give the fan a “idle” voltage?

If I did go this route then the Noctua A6x25 should be fine as it wouldn’t be able to stall with that voltage applied? I see from another post that 1200RPM is the minimum, so if I were to set that with iStat then read what voltage it’s applying. I could subtract it from the 12v constant and that’s what resistor I’d need? I hope that isn’t confusing

I want to be able to run any OS without the worry of fan controls or needing them on every single one. So essentially how it is stock. I don’t mind narrowing it in with a multimeter.

 

[arw]

as long as the CPU diode is below 51℃ the XR-2 is stalling.
After the Macs Fan Control first intervenes at 51℃, it will work stably even if it is below 51℃ later.

The stalling is probably because you are overriding the minimal SMC speed of 1112 rpm with Macs Fan Control to 800 rpm?
Any particular reason you're not using SMC auto or at least raise the 800 to sth more moderate?
Also, under load, SMC handles the fans quite differently:
With replaced NF-S12B redux-1200 as intake & exhaust these are the speeds after 1 hour of Cinebench.
(Dual x5690, stock boosters, CPU_A Tdiode 81°C, CPU_B Tdiode 69°C)

I want to be able to run any OS without the worry of fan controls or needing them on every single one. So essentially how it is stock. I don’t mind narrowing it in with a multimeter.

Ok, I hope I understand correctly:
If you replace your stock fans with confirmed 3-pin ones, this is exactly how it will still behave (auto-controlled, OS independent).

so if I want to do without fan control(setting a minimum rpm), my best route would be piggybacking off the Mac Pro’s 12v(4th wire?) with a resistor to give the fan a “idle” voltage?

Instead of (mis-)using an original fan connector (I don't know the current it can deliver), I'd better get the 12 V from a.e. a SATA connector with a matching adapter. Then simply use Low-Noise-adapters.
Or, if you're into soldering, instead of a fixed value resistor, use a mini DC-DC buck converter like the MP1584EN.

EDIT: Your post got me thinking. One would need a simple circuit that:
Feeds (let’s say) 6V fixed into the fan but as soon as Vc of the Mac Pro fan header exceeds that value, that one takes over/dominates. Something with diodes and transistors… Too bad it‘s above my head.
It would mean we could replace the fans with any model we desire AND make use of the SMC.

 

[jo666]

I additionally recommend removing the fan guards (Intake, Exhaust & PCI) for even quieter and better cooling thanks to the reduced air resistance.

for intake and exhaust: did you cut out the guards with saw or something?
pcie guards can simply removed by unmounting the outer housing with the guards so no mod needed…

I also read in this thread that open the dvd lid permanently will help too…
are there other things that we can do to further optimise the cooling condititions of our cMP?

 

[Bootso]

The stalling is probably because you are overriding the minimal SMC speed of 1112 rpm with Macs Fan Control to 800 rpm?
Any particular reason you're not using SMC auto or at least raise the 800 to sth more moderate?
Also, under load, SMC handles the fans quite differently:
With replaced NF-S12B redux-1200 as intake & exhaust these are the speeds after 1 hour of Cinebench.
(Dual x5690, stock boosters, CPU_A Tdiode 81°C, CPU_B Tdiode 69°C)
View attachment 2168703

Ok, I hope I understand correctly:
If you replace your stock fans with confirmed 3-pin ones, this is exactly how it will still behave (auto-controlled, OS independent).

Instead of (mis-)using an original fan connector (I don't know the current it can deliver), I'd better get the 12 V from a.e. a SATA connector with a matching adapter. Then simply use Low-Noise-adapters.
Or, if you're into soldering, instead of a fixed value resistor, use a mini DC-DC buck converter like the MP1584EN.

EDIT: Your post got me thinking. One would need a simple circuit that:
Feeds (let’s say) 6V fixed into the fan but as soon as Vc of the Mac Pro fan header exceeds that value, that one takes over/dominates. Something with diodes and transistors… Too bad it‘s above my head.
It would mean we could replace the fans with any model we desire AND make use of the SMC.

Maybe..
Due to the fact that on auto the NF-A6x25 FLX has sopped. NF-A6x25 FLX does not like 1112 rpm, since a minimum 1600 rpm is required, that's why it stops.
XR-2 is more stable overall - 1112 rpm is OK
I just tried it and it works on auto

 

[jo666]

for intake and exhaust: did you cut out the guards with saw or something?
pcie guards can simply removed by unmounting the outer housing with the guards so no mod needed…

I was wrong about removing the PCIe guards is that easy… postponed for now.
I removed the dvd lid, the intake and exhaust guards. works great, iam pretty happy now.
at idle and with my custom Mac fan control setting, all I can hear now is just the boosters and and my gpu (a sapphire rx 560).

would it make sense to separately cool the northbridge? I think about adding a small fan to ease the intake… seems
intake has to run quite heavy to get the nb temps down.
or do you think the s12b fans instead of the uln used as intake fan will make a difference here?

also is there fan app to set minimum temps? Mac fan control can't do this…

I also read in this thread that open the dvd lid permanently will help too…
are there other things that we can do to further optimise the cooling condititions of our cMP?

 

[hwojtek]

I also read in this thread that open the dvd lid permanently will help too…

No, it won't do anything. The OD compartment is separated from the airflow.

 

[jo666]

sure, I forgot to say that I removed the dvd compartment. so there is airflow from the front to the psufan thru the psu and finally the back of the cMP.

 

[Minimum91]

Since this thread is still seeing some action I decided to update. I used my single CPU Mac Pro with all aforementioned fans in this thread for a while, but was still not satisfied with the CPU cage Boosta fan noise levels, especially when it was ramping up and down RPMs, so I swapped the Noctua NF-R8 redux-1800 for a NF-B9 Redux-1600 by placing it in the front of the CPU cage as seen in the pictures. First I tried it to place flat out in front of the CPU cage and was already much better in terms of humming frequency characteristics, but then I read online that placing the fans in such close proximity causes extra air turbulence noise (just as with the plastic Intake and Exhaust fins which I have already removed) so I moved it away about one centimetre from the cage and stuck it (albeit not in a very visually appealing way) with some dampening material to lessen the vibrations even more. The temperatures might have dropped by a degree or so. It definitely did not make it worse, nor significantly better. I can finally say that I am entirely satisfied.

Attaching a video (in parts: Start up | Fan ramp up to max | 30 second ramp down) recorded on my iPhone 13 mini with a Lightning stereo Zoom microphone attached, and set to maximum sensitivity. If it appears loud, it's because the Mic is right in the middle between the CPU section fans, otherwise it's inaudible up to 1300RPMs and then becomes ever so slightly audible, but I no longer hear odd frequency jumps when it ramps up. The machine is under the desk and if ever the fans ramp up, which is rarely with my use, it produces a very pleasing acoustic characteristic, unlike with the NF-R8.

 

[jo666]

nice one! thanks for sharing. care to go into some detail about the dampening material that you use? I can see duct-tape…
did you made a ab-comparision before and after the the mod?

and because you mentioned that you have your cMP under the table:
I had an interesting experience today when I tested my new noctua fans in my dual core 5,1 (replaced all except the cpu fans) that is placed under my table as well. as you described I could hear a clear low frequency humming of the fans as I sat on the table. when I moved my chair back from the table (for lets say 1 meter) and listed again the hum was gone. a friend who also has a cMP under his table told me the same thing. iam not sure if the resonance of the cMP is and reinforced by table … but the first thing that I will do tomorrow is move my cMP 1m behind the table to hear how that sounds.

 

[Minimum91]

@jo666

Hah, I almost forgot, but I do have the audio with NF-R8 redux-1800 as boosta recorded, except it was recorded from the front of the machine, instead of the side with the side panel open and it might have used a different Mic sensitivity setting. That whiny noise (from about 500hz to 2000hz) you hear in the recording when the fans ramp up - that's the NF-R8. And it no longer there with the NF-R9.

The dampening material was a piece of foam that was inside a professional graphic pencil case I have since about 15 years ago. I figured, since it has already survived this whole time, it might survive a little more for this function. The duct-tape is aluminium foil tape. It's extremely sticky and you can bend it to your liking and it stays that way, unless you bend it again.

From my experience - all of the original Mac Pro fans are a bit hummy, especially the stock CPU ones and the PCI fan coming in a close second place. Actually, after replacing all the fans with Noctuas, I found a guy selling a NOS Mac Pro 5,1 case locally, with all original and completely new fans, still wrapped in plastic. I bought the PCI fan, as I was a bit unhappy with how the Noctua was producing significantly less airflow at the time. As soon as I installed the stock fan and booted - Instantly I could hear annoying humming that was mostly gone when I did this mod. Needless to say I removed the stock PCI fan and went back to using the Noctua. I solved the airflow problems differently.

 

[jo666]

@jo666

Hah, I almost forgot, but I do have the audio with NF-R8 redux-1800 as boosta recorded, except it was recorded from the front of the machine, instead of the side with the side panel open and it might have used a different Mic sensitivity setting. That whiny noise you hear in the recording when the fans ramp up - that's the NF-R8. And it no longer there with the NF-R9.

The dampening material was a piece of foam that was inside a professional graphic pencil case I have since about 15 years ago. I figured, since it has already survived this whole time, it might survive a little more for this function. The duct-tape is aluminium foil tape. It's extremely sticky and you can bend it to your liking and it stays that way, unless you bend it again.

From my experience - all of the original Mac Pro fans are a bit hummy, especially the stock CPU ones and the PCI fan coming in a close second place. Actually, after replacing all the fans with Noctuas, I found a guy selling a NOS Mac Pro 5,1 case locally, with all original and completely new fans, still wrapped in plastic. I bought the PCI fan, as I was a bit unhappy with how the Noctua was producing significantly less airflow at the time. As soon as I installed the stock fan and booted - Instantly I could hear annoying humming that was mostly gone when I did this mod. Needless to say I removed the stock PCI fan and went back to using the Noctua. I solved the airflow problems differently.

yes, I can hear the hum that you solve with our mod. its obvious.
to bad that dual cpu trays don't have the necessary place to do that - its cramped.

did you solved your pcie fan problem by removing the fan guards?

 

[Minimum91]

yes, I can hear the hum that you solve with our mod. its obvious.
to bad that dual cpu trays don't have the necessary place to do that - its cramped.

did you solved your pcie fan problem by removing the fan guards?

My PCI Fan problem was actually a GPU cooling problem and here is my ridiculous solution. I wish I had better materials at hand, but this is pretty thick and sturdy graphic paper. Same foil tape is used here. Some day I will get better materials to do this, but right now, this is serving the purpose very well. My inspiration was sort of how the 2019 Mac Pro GPU modules solved this. The results are absolutely incredible. The GPU can now be cooled at extremely low RPMs when actively used with almost no additional noise vs idling. I also reversed the direction of one of the fans. As a side effect of this mod, the NVMe SSD is also now running cooler by about 4 degrees, because the heated air from the GPU gets diverted out the back of the machine. I more ideas how to better solve this, but that would require modelling and a 3D printer which I don't have and probably won't have in the near future as I just don't have the space for it.

 

[jo666]

during my tests with my new fans I noticed that the processor cage resonates and emanates a low frequency humming. surprise - the pci-e fan housing directly sits on top of the proc cage and the faster fan spins the louder the humming, no damping.
a quick test proves it: I completely removed the fan housing and put the fan on a piece of rubber wich I than put back to the original spot on the proc cage and plugged the connector to the backplane board. this takes off almost all of the humming that my mac emanates.

(maybe) a sideeffect:
doing the fan tests without the pci-e fan housing I noticed a 10% higher temp reading for the PSU.
does this somehow relates to the magnetic strip on the backside of the pci-e housing?

 

[hwojtek]

How about putting a thick foam tape in space indicated on the picture?

 

[jo666]

yes, I already tried it. but there is not much space between the housing and the cage... so if we want to use the fan in the housing one has to find a very thin foam or cut the lower side of the housing (I want to remove the fan guards anyway).

 

[Iagus]

I've been reading this awesome thread for the past weeks. Thanks to all who have contributed.

I own a cMP 5,1 dual cpu tray mid 2012 which has become too nosiy for my needs.

Has anyone other than @Bootso had success with the Noiseblocker Blacksilent XR-2 60mm as replacement fans for the Boosters A nd B? Of course, doing the pin swap method and working with SMC.

Just trying to confirm if the XR-2 can be considered as "tested" and working properly before I purchase them.

Thanks!

 

[Bootso]

I recommend this video!
My geekbench 4 score was 55000 points.
After I did what is in the video I got 129000 points!!!Increase GPU performance

 

[Bootso]

I've been reading this awesome thread for the past weeks. Thanks to all who have contributed.

I own a cMP 5,1 dual cpu tray mid 2012 which has become too nosiy for my needs.

Has anyone other than @Bootso had success with the Noiseblocker Blacksilent XR-2 60mm as replacement fans for the Boosters A nd B? Of course, doing the pin swap method and working with SMC.

Just trying to confirm if the XR-2 can be considered as "tested" and working properly before I purchase them.

Thanks!

I bought three sets,

2x NB-BlackSilentFan 60x60x25 XR-2 - winner
2x NF-A6x25 FLX
2x NB-BlackSilentPro 60x60x25 PR-1

Tried all three, changed them 4 times before I finally decided to use the Blacksilent XR-2 and have been using it ever since, perfect.

In half a year I have had to restart 2 times because they started working max sped. I have since cleaned up my hard drive and have had no problems since. It is important to always have twice as many GB of free space on the SSD as there is memory on the machine.

I have 96 GB of memory and my 1 terabyte ssd was full. I cleaned up the ssd and installed Monterey 12.7.1 and everything is running smoothly again. Now I have 500 GB free space on the machine.

and set the SMBIOS Spoof level in OpenCore to none, then install OpenCore

I've been using fan contorol on automatic and it works fine after I cleaned up the SSD.

 

[arw]

2x NB-BlackSilentFan 60x60x25 XR-2 - winner

Great to hear you found a viable replacement!
- Do you know the minimal fan speed before they stall? If not, could you please temporarily (!) decrease the fan speed manually with Macs Fan Control so I can add it to the overview?
- As you have Dual x5690, I'm interested if they can be adequately cooled with the XR-2 under sustained load. Do you have any temperatures for running yes or Cinebench Multicore for several minutes?
(I'm asking because the original fans can do 5200 rpm vs. the 2200 of the XR-2)

 

[Iagus]

I bought three sets,

2x NB-BlackSilentFan 60x60x25 XR-2 - winner
2x NF-A6x25 FLX
2x NB-BlackSilentPro 60x60x25 PR-1

Tried all three, changed them 4 times before I finally decided to use the Blacksilent XR-2 and have been using it ever since, perfect.

In half a year I have had to restart 2 times because they started working max sped. I have since cleaned up my hard drive and have had no problems since. It is important to always have twice as many GB of free space on the SSD as there is memory on the machine.

I have 96 GB of memory and my 1 terabyte ssd was full. I cleaned up the ssd and installed Monteray 12.7.1 and everything is running smoothly again. Now I have 500 GB free space on the machine.

and set the SMBIOS Spoof level in OpenCore to none, then install OpenCore

I've been using fan contorol on automatic and it works fine after I cleaned up the SSD.

Thanks for responding @Bootso ! That's good to know.

I have plenty of free space on the HD. My OS is Mountain Lion (it works to satisfy my needs as I keep things really simple).
Do you think that would matter at all when replacing the old fans with new ones? I suppose most of the people commenting in this thread have more recent OS than mine, in your case, Monterey 12.7.1.

As for the SMBiOS Spoof level, although I watched the video you linked, I'm completely new to that. So thanks for that too!

 

[Bootso]

Great to hear you found a viable replacement!
- Do you know the minimal fan speed before they stall? If not, could you please temporarily (!) decrease the fan speed manually with Macs Fan Control so I can add it to the overview?
- As you have Dual x5690, I'm interested if they can be adequately cooled with the XR-2 under sustained load. Do you have any temperatures for running yes or Cinebench Multicore for several minutes?
(I'm asking because the original fans can do 5200 rpm vs. the 2200 of the XR-2)

I reduced the fan speed to 800 rpm for a few minutes. The fans do not stop at 800. They stop around 633-650 rpm.
But you can also see in the picture that at 800 the EXHAUST and INTAKE compensate, automatically increasing.
I did the stress test for 10 minutes look at the pictures.

In half a year I have had to restart 2 times because EXHAUST and INTAKE started working max sped.
And BOOSTA and BOOSTB have stopped. Before they stopped rotating at 633-650 rpm.
I know this from remembering. Because TG Pro shows BoostB rpm and Macs Fan Control shows boostA rpm in the menu bar. In both cases, the machine was in sleep mode for several hours and happened immediately after waking up.

but since then I've been paying attention to that, and OpenCore has been updated and the most stable OS on the machine is Monterey. But of course I have 2 x 3,46 GHz 6-Core Intel Xeon and 96 GB 1333 MHz DDR3

////////////////////
2x NF-A6x25 FLX -->> max one hour after startup, they both stopped
2x NB-BlackSilentPro 60x60x25 PR-1 -->> few minutes after startup, they both stopped
true for both - did not work stable, stalling in dual tray. After starting, alternately one or the other would work, or one would not start at all. But on average, it could be said that after an hour of use at most, both would stop.

//////////////////
BlackSilentFan 60x60x25 XR-2 - winner
simply works as it should in dual tray

 

[Bootso]

Thanks for responding @Bootso ! That's good to know.

I have plenty of free space on the HD. My OS is Mountain Lion (it works to satisfy my needs as I keep things really simple).
Do you think that would matter at all when replacing the old fans with new ones? I suppose most of the people commenting in this thread have more recent OS than mine, in your case, Monterey 12.7.1.

As for the SMBiOS Spoof level, although I watched the video you linked, I'm completely new to that. So thanks for that too!

Welcome to the club!

I am a do-it-yourself person and I had fun changing the fans. And does it matter? It was annoying to me that the machine was as loud as if I was in a server room. I'm happy to use it since it's quiet.

I replaced/installed:
I first replaced all the fans with brand new factory ones in 2018. But it has not become quieter. 🙈
2 x 3,46 GHz 6-Core Intel Xeon
96 GB 1333 MHz DDR3
Mac Pro External Bluetooth Antenna Kit
USB 3.0 PCIE Card
All fans to silent.
1 x Noctua 92 x 92 x 25mm NF-B9 redux-1600 rpm - 3 Pin
3 x Noctua 120 x 120 x 25mm NF-S12B redux-1200 rpm - 3 Pin
2 x NB-BlackSilentFan 60 x 60 x 25mm XR-2 - 2200 rpm - 3 Pin
AMD Radeon RX 580 8 GB
1TB SSD + 2TB SSD Backup disc
OpenCore + Monterey 12.7.1

I started building it in 2018 and it was finished in 2023.
And don't ask how much it was, because it was a lot.
But now that everything has been replaced, MACPro 5.1 is a very good machine.
Now I'd prefer to buy an M2 Pro Mac Mini or Mac Studio m2 or ultra instead of building a MacPro5.1.

 

[reppresident]

I recommend this video!
My geekbench 4 score was 55000 points.
After I did what is in the video I got 129000 points!!!Increase GPU performance

excuse me,

i've saw the video of changing a spoof level of oclp from minimum to none on the cMp's increasing the gpu performance in over 30%, wow!!

but nothing said about the cons of this change or any function that this will afect.

could you kindly help me with some more info about it?

im on cmp 5.1 with oclp 0.4.11 and monterey 12.7

thanks anyway.

 

[arw]

but nothing said about the cons of this change or any function that this will afect.
could you kindly help me with some more info about it?

https://forums.macrumors.com/threads/manually-configured-opencore-on-the-mac-pro.2207814/post-31696708

https://forums.macrumors.com/threads/manually-configured-opencore-on-the-mac-pro.2207814/post-31697370

Spoofing is required to enable GPU hardware acceleration (video encode/decode).
As well as for other different features (like Continuity) or multi-screen video output.

 

[reppresident]

https://forums.macrumors.com/threads/manually-configured-opencore-on-the-mac-pro.2207814/post-31696708

https://forums.macrumors.com/threads/manually-configured-opencore-on-the-mac-pro.2207814/post-31697370

Spoofing is required to enable GPU hardware acceleration (video encode/decode).
As well as for other different features (like Continuity) or multi-screen video output.

So, dont know why they make this looks a promising benefit change. thank you for clarifying this to me