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acurtis

macrumors newbie
Original poster
Jun 25, 2020
8
1
Hi all. been searching the threads for a little help here. I have a Mac Pro 6,1 Late 2013, Trashcan, It was running Catalina with 6-core CPU, 1tb SSD from owc, 128gb of memory and the dual AMD Firepro d700s. I thought i would give it a little more beef with purchasing the 12-core cpu off OWC. Install went smoothly but I turned on the computer and the fan was going full blast, huge kernel task load using up all of the CPU and it was very sluggish. I didn't reset my PRAM stupidly, and tried to do a OS reboot from internet recovery. IT failed.

So i took it apart again, reinstalled my 6-core cpu, took off the GPUS and added fresh thermal paste, tried to fire it back up and the same thing happened, massive Kernal Tasks cpu usage. So I keep trying to reset SMC, PRAM, internet recovery, USB boot with Catalina, USB boot with Mojave, I've wiped the HD, put in the original MAc 500gb SSD, and I can't get any install to take. Basically it loads very slowly and then says either "Finishing up in less that a minute" or Finished and now it will restart your computer. Well the computer shuts down and then doesn't start back up on its own.

I ran an Apple Diagnostic test, and it says there is an issue with the SMC. What can I do? there is no apple store within 300 miles and the one repair guy shut down due to covid. thanks everyone!
 

tsialex

Contributor
Jun 13, 2016
13,454
13,601
Hi all. been searching the threads for a little help here. I have a Mac Pro 6,1 Late 2013, Trashcan, It was running Catalina with 6-core CPU, 1tb SSD from owc, 128gb of memory and the dual AMD Firepro d700s. I thought i would give it a little more beef with purchasing the 12-core cpu off OWC. Install went smoothly but I turned on the computer and the fan was going full blast, huge kernel task load using up all of the CPU and it was very sluggish. I didn't reset my PRAM stupidly, and tried to do a OS reboot from internet recovery. IT failed.

So i took it apart again, reinstalled my 6-core cpu, took off the GPUS and added fresh thermal paste, tried to fire it back up and the same thing happened, massive Kernal Tasks cpu usage. So I keep trying to reset SMC, PRAM, internet recovery, USB boot with Catalina, USB boot with Mojave, I've wiped the HD, put in the original MAc 500gb SSD, and I can't get any install to take. Basically it loads very slowly and then says either "Finishing up in less that a minute" or Finished and now it will restart your computer. Well the computer shuts down and then doesn't start back up on its own.

I ran an Apple Diagnostic test, and it says there is an issue with the SMC. What can I do? there is no apple store within 300 miles and the one repair guy shut down due to covid. thanks everyone!

Maybe it's not your problem, but check the BT connection, when the cable is not connected correctly or damaged, polling is so intense that everything becomes sluggish.

This post has the Apple Technician Guide for late 2013 Mac Pro:

 
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acurtis

macrumors newbie
Original poster
Jun 25, 2020
8
1
Thanks I will order it. I had a faster install of high sierra but it still hasn't successfully restarted. Maybe I need to change the start up disk permissions? Do we think maybe if I just buy a new power supply unit that would work or did I cook my gpus with the 12 core

Maybe it's not your problem, but check the BT connection, when the cable is not connected correctly or damaged, polling is so intense that everything becomes sluggish.

This post has the Apple Technician Guide for late 2013 Mac Pro:

 

tsialex

Contributor
Jun 13, 2016
13,454
13,601
Thanks I will order it. I had a faster install of high sierra but it still hasn't successfully restarted. Maybe I need to change the start up disk permissions? Do we think maybe if I just buy a new power supply unit that would work or did I cook my gpus with the 12 core
If you don't have artefacts, no.

Check every connection, maybe it's just something that you are overlooking.
 

acurtis

macrumors newbie
Original poster
Jun 25, 2020
8
1
If you don't have artefacts, no.

Check every connection, maybe it's just something that you are overlooking.
I have artifacts when the screen loads sometimes. Just got high sierra to install. Took forever. And it's going super slow. But it's a start. Here is a picture of my activity monitor. CPU load is huge but I dont see kernal tasks anymore.
 

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KeesMacPro

macrumors 65816
Nov 7, 2019
1,453
596
CPU load is huge but I dont see kernal tasks anymore.

The screenshot only shows user activity .
Maybe you could set activity monitor to "show all processes" to see all activity (It's set to "my processes" )
 
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tsialex

Contributor
Jun 13, 2016
13,454
13,601
Be meticulous and follow every step to of the diagnostic process on the Apple Technician Guide, then run ASD 3S159.

ASD 3S159 is the Apple internal diagnostics tool, you will have to search a little for it.
 

h9826790

macrumors P6
Apr 3, 2014
16,656
8,587
Hong Kong
Sounds like you didn’t apply thermal paste correctly (e.g. haven’t completely clean the CPU or heatsink before apply the new paste).

Full fan speed and high kernel task both fit the symptoms of CPU overheating. That kernel task highly likely is inserting the halt command to reduce actual CPU loading to cool down the CPU. Also, due to high temperature, the CPU is seriously downclocked, that’s why it’s supper slow.

You better shut down the 6,1 ASAP, and check the CPU installation / cooling system again.

If you 100% sure you did that correctly, then you better check the CPU temperature (e.g. via MacsFanControl). If the temperature is low, and SMC reset doesn’t help. Then very likely the logic board is failed (or damaged during CPU upgrade)
 
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acurtis

macrumors newbie
Original poster
Jun 25, 2020
8
1
Sounds like you didn’t apply thermal paste correctly (e.g. haven’t completely clean the CPU or heatsink before apply the new paste).

Full fan speed and high kernel task both fit the symptoms of CPU overheating. That kernel task highly likely is inserting the halt command to reduce actual CPU loading to cool down the CPU. Also, due to high temperature, the CPU is seriously downclocked, that’s why it’s supper slow.

You better shut down the 6,1 ASAP, and check the CPU installation / cooling system again.

If you 100% sure you did that correctly, then you better check the CPU temperature (e.g. via MacsFanControl). If the temperature is low, and SMC reset doesn’t help. Then very likely the logic board is failed (or damaged during CPU upgrade)
Thanks for responding!. I watched so many videos about applying paste I think I did ok. But I will take another shot at it. I downloaded tg pro app to show me sensor temps and allow me to control the fan. Although I did think that I had a faulty sensor they dont have any error reports coming from the app.

More paste? Less paste?
 

h9826790

macrumors P6
Apr 3, 2014
16,656
8,587
Hong Kong
Thanks for responding!. I watched so many videos about applying paste I think I did ok. But I will take another shot at it. I downloaded tg pro app to show me sensor temps and allow me to control the fan. Although I did think that I had a faulty sensor they dont have any error reports coming from the app.

More paste? Less paste?
Can you see all temperature readings from TG Pro?

If any CPU related temperature reading is missing. The SMC may also treat it as overheating (fail safe).
 

tsialex

Contributor
Jun 13, 2016
13,454
13,601
This is probably not thermal related at all, you can install without any paste and wouldn't have kernel task problems while will have it to the roof if you have any connection problems between the several interconnections.

One frequently overlooked is the data connection to the WiFi and BT module or the uFL to the antenna.

IVRN5AI1HXUn3cI1
 

acurtis

macrumors newbie
Original poster
Jun 25, 2020
8
1
Thanks. I looked at that quickly and everything seemed securely plugged in. I dont have a multi meter to check the integrity of the systems maybe that's my next step.
[automerge]1593279368[/automerge]
Maybe you could post a screenshot of TG Pro readings?
Thanks. I will post a photo, if my memory serves me correctly everything was right around 35c except for something in the power unit was ready 50c. It's my work computer so I shut it down and left it for the weekend. Right before I left o was trying to boot usb install Mojave from the high sierra and it wasn't getting past the choosing language step.
 
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MisterAndrew

macrumors 68030
Sep 15, 2015
2,895
2,390
Portland, Ore.
Someone else made a thread about having problems after installing a CPU here: https://forums.macrumors.com/threads/mac-pro-6-1-cpu-upgrade-shutting-off-at-login-screen.2241342/

I think people should stop trying to do DIY CPU upgrades on these. Like how I explained in that thread, the 6,1 Mac Pro is not your typical desktop computer. It requires special handling and special equipment for proper repairs. You should have the correct knowledge and tools before making repairs. There is probably also a good reason Apple does not consider the CPU replaceable by itself. It is only available pre-installed on a new CPU riser card. Perhaps the new CPU isn't situated correctly or the screws have not been torqued to the proper setting. Some component like a flex cable could have also become damaged when the machine was worked on.
 

acurtis

macrumors newbie
Original poster
Jun 25, 2020
8
1
You are right. All the tutorials I saw online made it look easy. Followed the directions as carefully as I could but clearly something went wrong
 

MisterAndrew

macrumors 68030
Sep 15, 2015
2,895
2,390
Portland, Ore.
Well none of those tutorials were produced by Apple and should not be followed. Only the official instructions from Apple tsialex referenced should be followed, but of course there is no torque spec listed for the CPU to the riser card since they are not intended to be separated by an Apple Store technician. So you’ll have to use your best judgment. The torque spec for the riser card to the core is probably fine for those.
 

mgaa80

macrumors newbie
Jun 21, 2015
5
4
I may have some answers for people who have this issue. Basically what happens here (at least that was it in my case) SMC cannot read one or more sensor information and so the fans go full blast (because the mac wants to protect itself from possible overheating) and the kernel_task process blocks the system, so the cpu doesn't heat up too much.

You can deactivate the kernel_task by basically deactivating the thermal management of your mac (https://www.davidschlachter.com/misc/kernel_task). This will restore full speed of the CPU - but will not resolve fan at full blast. You may be able to control this with a individual fan control software once booted into MacOS.

What you can do:
Start onboard diagnostics (https://support.apple.com/en-us/HT202731) and determine where the problem is exactly. You can also use ASD Tools (for MacPro 6,1 you need ASD 3S159) to test every specific sensor and determine exactly where the problem is.


If you have a reference code PFM006 / PPN001 from Apple Diagnostics or the sensor TA0p (Ambient MLB) is not responding while tested with ASD 3S159 - the next passage is for you:

Bad news.

UPDATE:
Likely your Logic board is damaged and not repairable for the average person.And here is what's likely happened (and this is exactly what happend to me):

While removing one of the three big connector from the logic board (the round board in the bottom) by hand I ripped off an ultra small SMD component. This is (according to my analysis) one component the SMC needs to read from TA0p sensor. See image attached - i ripped off the component that you'll see in the picture (picture is from my replacement board)


You also need to be very careful while unmounting the CPU board - because you can damage this, too.
While unscrewing the CPU Board from the heatsink you have to first remove the outer four T-10 screws. These screws are screwed in into stand-offs which themselves are screwed into the main heatsink. If you are lucky you can remove the screws with no issue - but (if you're not so lucky) by loosening the screwes the standoff (and not the screw) can come loose and is then rotating and rubbing on the CPU Board surface as you are unscrewing the screw. This is how I managed to damage my board - luckily the damage was not so huge - the CPU board could be saved...but yours could be defektive at that point. SO IF YOU REMOVE THE OUTER SCREWS MAKE SURE THE STANDOFF UNDERNEATH IS **NOT** rotating and you're ONLY unscrewing the T-10 screw itself.

In the MAC PRO 2013 service manual Apple *SPECIFICALLY* states that once even ONE SINGLE standoff comes loose the CPU board has to be sent to Apple for check/repair. This is likely due to the fact, that the CPU board could be already defective at that point.

So in the end you have to replace your Logic board (or find someone that can solder the SMD component back on - if you can find it) - or you deactivate thermal managemend and control the fans manually (as mentioned above). Of cource there can be other reasons - but I'm 99% positive that this was the isse in my case. I have a replacment CPU board coming in the next days - I will update this thread if I have news.

Best regards from Germany.
 

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MisterAndrew

macrumors 68030
Sep 15, 2015
2,895
2,390
Portland, Ore.
Thank you for the detailed and logical answer to this problem! That makes sense that is how people are damaging their Mac when replacing the CPU. Those who successfully replaced the CPU were indeed lucky that the standoff screws didn't rotate when they were loosening and tightening the screws. So that's why it's so critical to torque them to the exact spec.
 
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avro707

macrumors 68020
Dec 13, 2010
2,263
1,654
Upgrading the CPU is something I'm planning to do with my 2.4ghz 2695V2 Mac Pro, I have the 2697V2 2.7ghz processor on the way - this topic hasn't deterred me, it's just made me want to take more time and read as much information as I can. I've got the Apple technician document (the version converted to PDF) which I'll read through and I'm looking at as many videos online that I can before I do anything.

My idea is to max out the specs on that machine and keep the original processor as a spare.

Looks like I need to buy at least one particular wera torque screwdriver, it's available nearby where I am.
 

mgaa80

macrumors newbie
Jun 21, 2015
5
4
UPDATE guys. I finally found out what is the issue - AND updated my post from Thursday. Turns out, that I ripped off an SMD component from my Logic Board (not the CPU Board!). Although I damaged my CPU board as described on Thursday it is still functioning without any issue. Please read my post from Thursday again to find out what the issue was. Now I'm again 99% sure that this is and was the problem :)

One remark from my side:

I made two mistakes while upgrading the CPU in my MAC PRO 6,1 (described in my post from Thursday). BUT: I consider myself as a PC and MAC technician on a professional level. I did CPU swaps and logic board swaps for almost 50 MacBooks, Powermac G5's /MAC PRO 1,1 2,1 3,1 4,1 5,1. I did RAM and SSD upgrades (with logic board removal) on iMACs, MAC Minis, etc. Never with a SINGLE issue.

I'm repairing PC's now for almost 25 years and build and repaired well over 100 of them.

What I'm trying to say: I'm not a noob - if this can happen to me - It can happen to others, too.

The CPU swap in the MAC PRO 6,1 can be done even by relatively unexperienced persons - as long as you try to avoid (at least) the mistakes I did. Hope this helps anyone.

Greetings from Germany.
 

Smooghead

macrumors newbie
Sep 16, 2008
11
0
Been searching for 3S159 everywhere. The only downloads appear to be on


but despite downloading the .dmg files, none of them open. Any advice welcome thank you.

Do APPLE offer 3S159 anywhere ????

Thanks
 

TzunamiOSX

macrumors 65816
Oct 4, 2009
1,057
434
Germany
Been searching for 3S159 everywhere. The only downloads appear to be on


but despite downloading the .dmg files, none of them open. Any advice welcome thank you.

Do APPLE offer 3S159 anywhere ????

Thanks

This is a splitted DMG and you nee all 4 parts in the same folder to mount the dmg.
 
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