Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

rodedwards

macrumors regular
Original poster
Jul 7, 2010
208
69
Hi everyone ... I wonder if i can pick some brains?

I have a Mac Pro (2009) 4,1 flashed to 5,1 with latest firmware and boot ROM, running Mojave 10.14.6. I also have Samsung EVO 970 with 4 x internal HD, Radeon RX 580 Pulse (Mac flashed by MacStore UK) and 96Gb 1333 Mhz Ram with 2 x 3.46Ghz 6 core Intel Xeons.

I'm pushing my system processing 360 degree 8k video (basically 7680 x 3840 pixel dimensions) using latest FCPX and I seem to get random shut downs.

The GPU is largely maxed out, the CPU shows 1,300% for FCPX and the video Decoder (i guess maxed out). What concernes me, is that in big files the CPU tray and boxes get very hot to touch and Mac shuts down. The screen goes black, the white power light stays on and i have to press power button to shut off and reboot.

I'm not sure if i'm damaging the system pushing it so hard ... I wonder if it's the CPU temperature overheating that's the problem and if so, is there a way to limit the power or maybe increase the fan speed? I've just installed Macs Fan Control ... But no idea what settings to try.

Or is it power consumption too much?

I've opened the side panel to let heat escape when heavy processing but wonder what advice you all may give? I'm not a whizz with computers so a simple solution and advice would be appreciated if possible.

Big thanks ! :)

Screenshot 2020-07-10 at 07.23.12.png
 
Last edited:
Hi
I assume leaving all Fans on default ("auto") could lead to Thermal shutdown under heavy load.

-I've noticed something odd:
MacsFanControl doesn't show NorthBridge-Diode Temp....
Maybe you could reinstall it, because the Delta T of NB diode and T NB heatsink should not be more than ~15/20 degrees.
If it is , the NB heatsink rivets are broken, i recommend to check that first of all, unfortunately its a common issue.

- IMHO although it may seem a good idea to open the case letting cold air in, the airflow in especially the CPU case will not work as it is supposed to be which may result in even higher Temps.

-I recommend ,as many other MP4,1/5,1 users, to set the fans basically like this:
Intake and Boost A set depending on NB diode Temp : starting at ~50degrees , max rpm at ~ 80 degrees.
These 2 fans are the most effective to lower T for NB and CPU 1.
You could leave the other fans on auto.
In case PSU is running hot (caused by the GPU under heavy load) like over ~ 50 degrees, you could setup the PSU fan depending Supply2 ( lets say: 40- 70degrees)
In general you may tweak the settings adjusted to your workflow and load.
 
  • Like
Reactions: rodedwards
Hi
I assume leaving all Fans on default ("auto") could lead to Thermal shutdown under heavy load.

-I've noticed something odd:
MacsFanControl doesn't show NorthBridge-Diode Temp....
Maybe you could reinstall it, because the Delta T of NB diode and T NB heatsink should not be more than ~15/20 degrees.
If it is , the NB heatsink rivets are broken, i recommend to check that first of all, unfortunately its a common issue.

- IMHO although it may seem a good idea to open the case letting cold air in, the airflow in especially the CPU case will not work as it is supposed to be which may result in even higher Temps.

-I recommend ,as many other MP4,1/5,1 users, to set the fans basically like this:
Intake and Boost A set depending on NB diode Temp : starting at ~50degrees , max rpm at ~ 80 degrees.
These 2 fans are the most effective to lower T for NB and CPU 1.
You could leave the other fans on auto.
In case PSU is running hot (caused by the GPU under heavy load) like over ~ 50 degrees, you could setup the PSU fan depending Supply2 ( lets say: 40- 70degrees)
In general you may tweak the settings adjusted to your workflow and load.


That's all fantastically helpful ...

I just updated Macs Fans Control app and it now shows Northbridge Diode temp.

Having previously done an hour of intensive processing on old app, the Northbridge Diode temp showed 110C. I'm guessing that's not good !

Now i've reinstalled, I'll try your suggested settings and see how i get. Maybe after reinstall the fans will work and the temp will stay down.

If it is a problem with NB heatsink rivets broken - is that easy to fix or costly? Is it important to fix? I've no idea what they are ! :)

Big thanks !

Here is the Macs Fan Control app link for anyone who hasn't tried it : https://crystalidea.com/macs-fan-control

Screenshot 2020-07-10 at 09.28.18.png
 
I would shut down the MP immediately.
NB diode is 110!!!
NB Heatsink is 34 degrees.
These Temps should be in the same range within ~ 15degrees.
You'll have to remove the heatsink CPU1 to get access to the NB .
There are several threads here about how to repast the NB and replace the plastic rivets.

is that easy to fix or costly? Is it important to fix

Its not too difficult but some experience or preparation is strongly recommended.

Is it important to fix?
Yes, the NB will break if you keep using it without proper heatsink contact.
If it breaks, you'll have to replace the CPU board.

BTW: setting the fans to constant rpm overrules the SMC to increase fan speed in case of high Temps and is not recommended.
2000rpm for Intake/exhaust is a bit overkill and should not be necessary to keep Temps cool.
This must be very loud too..
 
Last edited:
  • Like
Reactions: rodedwards
I think it's beyond my skilllevel so will need to get repair.

I'll look into it.

Thanks again ... Hopefully i can get it fixed and stop a big repair.
 
YW.

This can be fixed , the rivets cost almost nothing.
It is not a very complicated operation , and for an experienced person ~ 30 min job.

Good Luck!
 
Yipes - The Northbridge Diode was 110c and cooked. Apparently the thermal paste was old and the heat sink clip was disconnected so it’s fried on my stress test. Had reconditioned board and the temps are no more than 85c with auto fans. Hopefully it’ll stop turning itself off ...
 
Yipes - The Northbridge Diode was 110c and cooked. Apparently the thermal paste was old and the heat sink clip was disconnected so it’s fried on my stress test. Had reconditioned board and the temps are no more than 85c with auto fans. Hopefully it’ll stop turning itself off ...
85ºC is still a lot, a reasonable temperature would be around 75ºC.
 
  • Like
Reactions: rodedwards
Thanks everyone ... Reconditioned processor tray was a bit of an expensive repair but hopefully it'll now stop randomly shutting down.

You guys were right ... dried up thermal paste was five years old and one of the plastic clips wasn't connected properly to the heat sink. This is why my Northbridge Diode reached 110c ! :oops: The repair shop www.create.pro had never known one so hot! :eek:

The temps already look much healthier as you all suggested. :)
 
Last edited:
Looking at the Temps at post #12:
I assume this is under load, not at idle ;)

Unless you don't mind to get the impression to be sitting next to a giant hairdryer, I would set the fans as follows:
-pci: auto
-ps: depending sensor PSMI supply 2: 45degrees min - 75degrees max rpm
-exhaust: auto
-intake : depending sensor NorthBridge DIODE: 50 degrees min- 75 degrees max rpm
-boost a: depending sensor NorthBridge DIODE: 50 degrees min- 75 degrees max rpm
-boost b: auto

This way the Temps should be lower and with a lot less noise...
 
  • Like
Reactions: rodedwards
Looking at the Temps at post #12:
I assume this is under load, not at idle ;)

Unless you don't mind to get the impression to be sitting next to a giant hairdryer, I would set the fans as follows:
-pci: auto
-ps: depending sensor PSMI supply 2: 45degrees min - 75degrees max rpm
-exhaust: auto
-intake : depending sensor NorthBridge DIODE: 50 degrees min- 75 degrees max rpm
-boost a: depending sensor NorthBridge DIODE: 50 degrees min- 75 degrees max rpm
-boost b: auto

This way the Temps should be lower and with a lot less noise...

BIG THANKS ! That's exactly what i wanted to know ...

I'll try them out and see how i get on.

Really appreciatre your input and knowledge :)))
 
  • Like
Reactions: KeesMacPro
My pleasure :)

Ofcourse after checking the T regularly you can tweak the values a few degrees up or down depending on the workload .
This way the fans are always depending on the Temps , and not fixed which involves the risk of cooking something.
 
  • Like
Reactions: rodedwards
Seems to be working like a dream atm ...

No unexpected shut downs even when outputting 8k video in FCPX, with Photoshop open, with 360 video stitching app rendering 8k video, Firebox browsing and Mac Mail open!

The temps never really went above 65, with max of 70 very occasionally.

I think this has given my Mac some more life. Once again ...thanks to you all.

Screenshot 2020-07-11 at 09.07.49.png
 
My pleasure :)

Ofcourse after checking the T regularly you can tweak the values a few degrees up or down depending on the workload .
This way the fans are always depending on the Temps , and not fixed which involves the risk of cooking something.

Just one more bit of advice if you would be so kind please ?! :)

I see my 'CPU A core from PCECI' sometimes runs hot about 82C. What's the best Macs Fan Control setting to get that down to more normal level please?

I tried tweaking several settings but not sure what i'm doing !

Thanks :)

Screenshot 2020-07-12 at 07.40.48.png
 
Just one more bit of advice if you would be so kind please ?! :)

I see my 'CPU A core from PCECI' sometimes runs hot about 82C. What's the best Macs Fan Control setting to get that down to more normal level please?

I tried tweaking several settings but not sure what i'm doing !

Thanks :)

View attachment 933133
My suggestion is to ignore that, it's meaningless for cMP now.

That should be "away from processor hot", which means, the higher the better. It works correctly on many softwares. But it seems MFC define that as something else, and use a different logic to present this parameter. Which is very meaningless for us now.
 
My suggestion is to ignore that, it's meaningless for cMP now.

That should be "away from processor hot", which means, the higher the better. It works correctly on many softwares. But it seems MFC define that as something else, and use a different logic to present this parameter. Which is very meaningless for us now.

Ahhhh - ok ! Thanks ... so just leave it to heat up and let fans take care of themselves?

My new CPU tray Northbridge Diode burn out was expensive repair and can't afford another !
 
It's up to you. There are many ways to make the NB run cooler.

But if I were you, I will also make the exhaust base on CPU A diode temperature, because CPU A always run warmer than CPU B
 
  • Like
Reactions: KeesMacPro
That should be "away from processor hot", which means, the higher the better. It works correctly on many softwares

I'm afraid you described something else like shown in e.g. TG Pro called "ProcHot".
Testing some Benchmarks with MFC the Temp 'CPU A core from PCECI' goes up .
I suppose it's showing Core T.
 
I'm afraid you described something else like shown in e.g. TG Pro called "ProcHot".
Testing some Benchmarks with MFC the Temp 'CPU A core from PCECI' goes up .
I suppose it's showing Core T.

So this is all ok?

This is all new to me, so please excuse my lack of knowledge.
Screenshot 2020-07-12 at 10.19.01.png
Screenshot 2020-07-12 at 10.18.33.png
 
I'm afraid you described something else like shown in e.g. TG Pro called "ProcHot".
Testing some Benchmarks with MFC the Temp 'CPU A core from PCECI' goes up .
I suppose it's showing Core T.
That's why I said ignore it in MFC. This parameter isn't presented correctly in MFC.
[automerge]1594546795[/automerge]
So this is all ok?

This is all new to me, so please excuse my lack of knowledge.View attachment 933154View attachment 933155
Unless you don't mind the fan noise, you can set the max temperature to 99°C.

It won't really make the CPU run at 99°C, but just for setting the fan profile. You can run stress test, the CPU shouldn't reach that max temperature (unless 100% fan speed still can't cool down the CPU, which should never happen on the cMP).

In fact, I setup my fan profile base on 120°C max temperature to minimise the fan noise.And my CPU still won't go above 80°C even in Prime95 stress test.
P95 low fan - clean.png
 
Last edited:
That's why I said ignore it in MFC. This parameter isn't presented correctly in MFC.
[automerge]1594546795[/automerge]

Unless you don't mind the fan noise, you can set the max temperature to 99°C.

It won't really make the CPU run at 99°C, but just for setting the fan profile. You can run stress test, the CPU shouldn't reach that max temperature (unless 100% fan speed still can't cool down the CPU, which should never happen on the cMP).

In fact, I setup my fan profile base on 120°C max temperature to minimise the fan noise.And my CPU still won't go above 80°C even in Prime95 stress test.
View attachment 933166

Thanks again ! Will give it a try ...
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.