Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
No problem. It's nothing wrong to do that.

The W3690 rated up to 101C (diode temperature, from the official intel diagnostic tool).
View attachment 832424

From memory, X5690 even rated up to 105C. IMO, as long as Turbo Boost still active, there is no noticeable benefit to cool down the CPU to below 70C, but shorten the fan's life, and have more fan noise.

But if that make yourself more comfortable, then of course you can do that, it won't hurt anything anyway. I don't think the fan is that easy to break also, especially you only occasionally stress the CPU.
I was actually quite discouraged when I upgraded my GPU to a GTX980 and threw a loaded Amfletec Squid into my 5,1. The first thing I noticed was the SMC reacted to that by raising my PSU fan to about 850 rpm and PCIe to about 1050 rpm from their default 600/800 rpm. It was noticable to me because I never really heard the fans before that but I'm used to their new default now and it's not too bad.

I'm a bit paranoid so I ordered all 4 Mac Pro fans for backup just in case any go bad in the future. I got a good deal of about $40 for them all and they look brand new.
[doublepost=1555720284][/doublepost]I'm still hoping to see the first person to hook up their 3rd party Northbridge fan with power from a PCIe card or an empty SATA port. If using a 5v fan you'd have to stepdown the voltage, perhaps with an inline resistor but it could be done. I think the advantage to that would be you could tuck the cable behind the backplane for a neater more permanent solution. That is after you guys get out of the testing phase and find a solution you're satisfied with.
 
I was actually quite discouraged when I upgraded my GPU to a GTX980 and threw a loaded Amfletec Squid into my 5,1. The first thing I noticed was the SMC reacted to that by raising my PSU fan to about 850 rpm and PCIe to about 1050 rpm from their default 600/800 rpm. It was noticable to me because I never really heard the fans before that but I'm used to their new default now and it's not too bad.

I'm a bit paranoid so I ordered all 4 Mac Pro fans for backup just in case any go bad in the future. I got a good deal of about $40 for them all and they look brand new.
[doublepost=1555720284][/doublepost]I'm still hoping to see the first person to hook up their 3rd party Northbridge fan with power from a PCIe card or an empty SATA port. If using a 5v fan you'd have to stepdown the voltage, perhaps with an inline resistor but it could be done. I think the advantage to that would be you could tuck the cable behind the backplane for a neater more permanent solution. That is after you guys get out of the testing phase and find a solution you're satisfied with.

That's the SMC fan bug. I believe your 5,1 is the 2009 model indeed.

You can simply stress the GPU a bit (e.g. run Luxmark for few seconds). Or run AirOut which is specifically build for this purpose. Or you can build your own fan profile in MacsFanControl to force the fans stay at the idle RPM you want.
 
That's the SMC fan bug. I believe your 5,1 is the 2009 model indeed.

You can simply stress the GPU a bit (e.g. run Luxmark for few seconds). Or run AirOut which is specifically build for this purpose. Or you can build your own fan profile in MacsFanControl to force the fans stay at the idle RPM you want.
Perhaps the SMC bug affects 5,1 too because I have a real 5,1. I bought it new from Apple in 2010 and my box says mid 2010. Unless Apple gave me a 5,1 CPU tray with a 2009 backplane and flashed the 5,1 firmware themselves. Is it possible that the SMC just acts the way it does do to the power demand of newer Graphics cards? I mean, my computer came with a ATI Radeon 5770 which only utilized one power connector in addition to the PCIe slot. The newer Graphics cards usually require two power connectors in addition to the slot. So I'd imagine that may change the behavior of the SMC particularly in the PSU and PCIe areas.
 
Last edited:
Perhaps the SMC bug affects 5,1 too because I have a real 5,1. I bought it new from Apple in 2010 and my box says mid 2010. Unless Apple gave me a 5,1 CPU tray with a 2009 backplane and flashed the 5,1 firmware themselves. Is it possible that the SMC just acts the way it does do to the power demand of newer Graphics cards? I mean, my computer came with a ATI Radeon 5770 which only utilized one power connector in addition to the PCIe slot. The newer Graphics cards usually require two power connectors in addition to the slot. So I'd imagine that may change the behavior of the SMC particularly in the PSU and PCIe areas.

From my own observation. The PCIe / PSU fan affected by both power draw and card's temperature.

Use both mini 6pin is not an issue, the stock 4870 / 5870 use both mini 6pin anyway. As long as low power draw during idle, the fans should able to stay at correct idle speed.

Since you mentioned the actual RPM, so, I expect you have some monitoring software. Did you check if the minimum fan speed still correct?

Also, did you try SMC reset yet?

I am very confident that the 980 won't be too warm during idle. But I am not familiar with the Amfletec Squid, not sure if this card can cause high fan issue.
 
From my own observation. The PCIe / PSU fan affected by both power draw and card's temperature.

That is what I thought too. I'd like to get to the bottom of this. Just to give you a little info: MP 5,1 (mid 2010) came with duel 2.4 GHz Quad core. Upgraded to duel X5690 with 64GB DDR3 1333 RAM. My NB rivets are like new and temps are normal so we can rule that out. Screen Shot 2019-04-21 at 1.25.59 PM.png

Since you mentioned the actual RPM, so, I expect you have some monitoring software. Did you check if the minimum fan speed still correct?

Using Macs Fan Control. Yes, the minimums are still the correct defaults. I noticed that there is no longer a temperature reading for my 980 like there was for the 5770. (No thermal sensor?). During a cold boot, once the OS loads the PCIe fans rev up to about 1200 RPM then settle at 1050 RPM but slightly fluctuates up and down. I'm not opening any programs to make it settle down, it just happens.

Also, did you try SMC reset yet?

Yes, a few times.

I am very confident that the 980 won't be too warm during idle. But I am not familiar with the Amfletec Squid, not sure if this card can cause high fan issue.

I'm going to try each card by themselves so see what is really happening but I'm pretty sure it's the GPU. The 980 is cool to the touch and it's own fan is quiet. I bought the 980 on Ebay and the seller claimed it was MVC flashed. Maybe it wasn't and it's a generic EFI/ bootloader. I know that it has a 2.5 GT/s link until I did the Cuda or 3D test like the MVC site says to do. It also does not report the RAM correctly in system profile. It gives me the total in MB and not GB. I have not flashed the Mojave BootRom yet (138 or 140). I stayed on the latest HS (89.BOO). Maybe that will fix the link speed unless that is truely a normal thing for NVIDIA cards.

EDIT: I just flashed 140 and the link speed did not change for the 980 and it still reports 4096MB RAM. All other cards report the correct 5GT/s link but they always have even with the BootROM that it shipped with in 2010.
 
Last edited:
That is what I thought too. I'd like to get to the bottom of this. Just to give you a little info: MP 5,1 (mid 2010) came with duel 2.4 GHz Quad core. Upgraded to duel X5690 with 64GB DDR3 1333 RAM. My NB rivets are like new and temps are normal so we can rule that out.View attachment 833208



Using Macs Fan Control. Yes, the minimums are still the correct defaults. I noticed that there is no longer a temperature reading for my 980 like there was for the 5770. (No thermal sensor?). During a cold boot, once the OS loads the PCIe fans rev up to about 1200 RPM then settle at 1050 RPM but slightly fluctuates up and down. I'm not opening any programs to make it settle down, it just happens.



Yes, a few times.



I'm going to try each card by themselves so see what is really happening but I'm pretty sure it's the GPU. The 980 is cool to the touch and it's own fan is quiet. I bought the 980 on Ebay and the seller claimed it was MVC flashed. Maybe it wasn't and it's a generic EFI/ bootloader. I know that it has a 2.5 GT/s link until I did the Cuda or 3D test like the MVC site says to do. It also does not report the RAM correctly in system profile. It gives me the total in MB and not GB. I have not flashed the Mojave BootRom yet (138 or 140). I stayed on the latest HS (89.BOO). Maybe that will fix the link speed unless that is truely a normal thing for NVIDIA cards.

EDIT: I just flashed 140 and the link speed did not change for the 980 and it still reports 4096MB RAM. All other cards report the correct 5GT/s link but they always have even with the BootROM that it shipped with in 2010.

Nvidia card run at 5GT/s regardless bootROM version and that reported link speed. That link speed change dynamically base on GPU usage in order to save power. Web driver will handle that.

Did you try AirOut yet?

Or you can create your own fan profile in MacsFanControl.

e.g.

PCIe fan base on PCIe ambient, min 38, max 55

PSU fan base on PSMI supply 2, min 38, max 55

This should allow your fan stay at correct idle, but spin up when required.
 
  • Like
Reactions: crjackson2134
Nvidia card run at 5GT/s regardless bootROM version and that reported link speed. That link speed change dynamically base on GPU usage in order to save power. Web driver will handle that.

Did you try AirOut yet?

Or you can create your own fan profile in MacsFanControl.

e.g.

PCIe fan base on PCIe ambient, min 38, max 55

PSU fan base on PSMI supply 2, min 38, max 55

This should allow your fan stay at correct idle, but spin up when required.
I tried AirOut today and it got the fans back down to defaults.

Do the older NVIDIA 680/780 cards behave similar to this or is this just with cards that don't have Native OS support?
 
I'm still hoping to see the first person to hook up their 3rd party Northbridge fan with power from a PCIe card or an empty SATA port. If using a 5v fan you'd have to stepdown the voltage, perhaps with an inline resistor but it could be done. I think the advantage to that would be you could tuck the cable behind the backplane for a neater more permanent solution. That is after you guys get out of the testing phase and find a solution you're satisfied with.
Mac_User0101

As a test, since last Thursday(Apr. 18th.) I've been powering my Northbridge fan ( 50mm x 50 x 10 ) from a spare USB 3.0 port on my Inatek KTU3FR-4P PCIe 4 port SATA powered USB 3.0 card. https://www.inateck.com/pci-express...-0-pci-express-karte-mit-4-usb-3-0-ports.html
No issues as power is supplied via the USB 3 cards SATA connection.

Everything cool and silent.
 
  • Like
Reactions: Mac_User 0101
crystallidea

( Love Macs Fan Control ! )

It appears to be a piece of bent stainless steel. It seems to be bent to stay in place but personally I would be worried about it dislodging and coming in contact with the CPU tray's PCB.

Any non-conductive, rigid material would be OK to deflect CPU B's fan's airflow.
 
Can anyone explain the drolson's concept please? Can't get from a photo... Is it a bended piece of steel? Dimensions? Installation photos? Thanks.


.016"X4"X10" Aluminum at the hardware or hobby, wrap the ends around a Xacto knife handle for the radius on the ends, bend it so it hooks on the corners and it will stay
 
Is there a place where I can view on how to reapply thermal paste to the north bridge? Not sure about the push pins being stock and my temps for Northbridge is 76c while idle no load. Ambient temps in the room it resides in is 23c.
I have upgraded the CPU's to the Mac to dual Intel Xeon X5690. CPU A is usually 16c higher than CPU B. But I read that is normal for a dual CPU.
 
peterc18st

My case ambient ( dual cpu tray ) is 34°C / 93.2°F,, The room ambient is 30°C / 86°F.
My Northbridge is at 58°C / 136.4F ( No airconditioner ).

More info here : https://forums.macrumors.com/thread...mp-reduction-in-dual-cpu-cmp-4-1-5-1.2179729/

I used the "Nut & Bolt" technique to secure the Northbridge heatsink; I use a hi-CFM fan to add extra, direct cooling of the NB heatsink.
Northbridge nut & Bolt setup 02.jpg

( you can use the original springs from the Northbridge rivets )

Thermal paste : I suggest you Google " Applying Northbridge Thermal paste " for tutorial videos; I did.

I smear just a little thermal paste onto both surfaces an and then a single small " grain of rice " sized drop of TP in the centre of the NB chip . . then bolt it down.

IMPORTANT : As my NB chip always runs much cooler than standard there is obviously less expansion/contraction with the heatsink so I can tighten the heatsink down a little more than the standard " spring rivet " tension.

CPU A & B : In my setup there is only an 8°C difference between CPU A & B. probably due to my USB powered NB heatsink fan. Your X5690s are 133w so probably run hotter than my two 5570s .

I highly recommend ( especially in summer ) removing the CPU tray and thoroughly de-dust it with canned air.
I also use a soft, non-conductive Japanese callirgraphy brush to go over the whole PCB & RAM.
 
Last edited:
peterc18st

My case ambient ( dual cpu tray ) is 34°C / 93.2°F,, The room ambient is 30°C / 86°F.
My Northbridge is at 58°C / 136.4F ( No airconditioner ).

More info here : https://forums.macrumors.com/thread...mp-reduction-in-dual-cpu-cmp-4-1-5-1.2179729/

I used the "Nut & Bolt" technique to secure the Northbridge heatsink; I use a hi-CFM fan to add extra, direct cooling of the NB heatsink.
View attachment 842445
( you can use the original springs from the Northbridge rivets )

Thermal paste : I suggest you Google " Applying Northbridge Thermal paste " for tutorial videos; I did.

I smear just a little thermal paste onto both surfaces an and then a single small " grain of rice " sized drop of TP in the centre of the NB chip . . then bolt it down.

IMPORTANT : As my NB chip always runs much cooler than standard there is obviously less expansion/contraction with the heatsink so I can tighten the heatsink dow a little more than the standard " spring rivet " tension.

CPU A & B : In my setup there is only an 8°C difference between CPU A & B. probably due to my USB powered NB heatsink fan. Your X5690s are 133w so probably run hotter than my two 5570s .

I highly recommend ( especially in summer ) removing the CPU tray and thoroughly de-dust it with canned air.
I also use a soft, non-conductive Japanese callirgraphy brush to go over the whole PCB & RAM.
Thank you for the reply.
How hard was it remove the plastic clips to put on the screw and bolt? I purchased replacement clips that work with the macpro and was wondering how hard it was to remove the old ones and put on new ones.
 
Thank you for the reply.
How hard was it remove the plastic clips to put on the screw and bolt? I purchased replacement clips that work with the macpro and was wondering how hard it was to remove the old ones and put on new ones.
You can "pinch" the bottom of them with a pair of pliers and push them UP & out.
 
get Northbridge temp down to 120 F ( 49c ) direct the airflow over the Northbridge HeatsinkView attachment 826579View attachment 826580

OP's heatsink patch really works!

I'm not sure why though. But I've gotten my Northbridge temp down from 70c to 48c. I am also using Macs Fan Control for fine tuning. My temps are:

CPU A Diode: 38c
CPU B Diode: 44c
IOH Diode (Northbridge): 48c

My settings are:

1. All fans except CPU B are set "Based on IOH Diode."
2. BOOSTB is set "Based on CPU B Diode."
3. PCI = 45-70c
4. PS = 40-60c
5. EXHAUST=40-65c
6. INTAKE=40-65c
7. BOOSTA=40-60c
8. BOOSTB=40-60c


Thanks drolson! Can you tell me what the patch is doing?
 
It seems to me that it would be easy to whip up a 3D printed snap-on airflow funnel to take the output from Heatsink A to blow over the Northbridge heatsink. Maybe something out of ABS or something of that nature...
 
It seems to me that it would be easy to whip up a 3D printed snap-on airflow funnel to take the output from Heatsink A to blow over the Northbridge heatsink. Maybe something out of ABS or something of that nature...
From what I can see though this redirection makes CPU-B warmer. I don't know which one is worst high T-diode or high CPU temp. Bear in mine CPU-B normally runs several degrees celsius colder than CPU-A (at least on mine)
 
From what I can see though this redirection makes CPU-B warmer. I don't know which one is worst high T-diode or high CPU temp. Bear in mine CPU-B normally runs several degrees celsius colder than CPU-A (at least on mine)

Why would it? We're only capturing the exhaust, not the intake. The Northbridge is cooled by this fan anyway - all we're doing is more effectively directing the airflow.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.