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kasuja00

macrumors regular
Original poster
Jun 3, 2018
101
64
Italy
Hi,

My Mac Pro has a big problem: it shutting down after a few minutes i turn it on.

It is a 5.1 mid 2012 version, with a Samsung SSD 850 evo on OWC accelsior S. GPU is the flashed EVGA GTX 780 in slot 1.

Yesterday when i turn it on it shutting down after 1, 2 minutes. I cleaned the ram contact and i boot the Apple Hardware Test disc and i run "Perform extended testing".
After 1 hour the test was passed ok.

But after the test i run Geekbench, and after 2-3 minutes it shut down.

What can it be? Have you got any suggestion? Thank you very much.
 
Hello there,

I would start by taking ram out, leaving minimal amount in. But it sounds like it's shutting down as a safety precaution - check the Northbridge rivet. Plenty of threads on this forum about that.

Cheers,

Razzerman
 
Heat issue. Download MacsFanControl and run Geekbench. Keep an eye on temps and take a few screenshots.
 
Hi,

My Mac Pro has a big problem: it shutting down after a few minutes i turn it on.

It is a 5.1 mid 2012 version, with a Samsung SSD 850 evo on OWC accelsior S. GPU is the flashed EVGA GTX 780 in slot 1.

Yesterday when i turn it on it shutting down after 1, 2 minutes. I cleaned the ram contact and i boot the Apple Hardware Test disc and i run "Perform extended testing".
After 1 hour the test was passed ok.

But after the test i run Geekbench, and after 2-3 minutes it shut down.

What can it be? Have you got any suggestion? Thank you very much.

Geekbench is very hard on your SSD. With certain SSD's it is advisable to restrict Geekbench to an absolute minimum.
I read that somewhere, this might be important. I would do this short list to make sure the SSD is at its max performance.

#1 See if Samsung has a new Firmware Update for the 850 Evo. If Yes, - Upgrade the Firmware
#2 Make a TimeCapsule Backup ASAP
#3 Reformat SSD and do a new install with MacOS
#4 Install Trim Enabler
#5 Check the Power draw on the GTX 780, an EVGA Power Link bracket might be advisable to balance power draw between both 6 + 6 or 6 + 8 pin for that GPU, depending which config you have.

That's what I would do
 
I had a similar problem and did all the troubleshooting steps imaginable but still the shut downs.

Brought it to Apple and they replaced the backplane card, mobo, video card, CPU tray, CPUs, and Airport card, but it didn’t resolve and gave me back the machine with all those brand new parts still installed and refunded all costs.

MacPartsOnine wanted a chance to fix it and he replaced the PSU and voila: problem solved.

I’m not saying your problems are caused by the exact same problem as mine, but I would tend to think it may be your PSU...
 
Hi,

Thank you, i posted an image of the temperatures when i run Geekbench. I run it with a minimal amount of ram (2 x 8 GB)
IMG_0971.jpg

Temperatures seems to be normal.
I booted from a normal hard disk and the Mac Pro has passed all the tests Geekbench CPU and compute Metal GPU.

Which SSD shoud i buy instead of Samsung 850?

The 780 GTX was powered by 2x 6pin -> 8 pin plus 2x sata to 6 pin. Now for the test i powered it with 1x 6 pin and 1x 6 pin -> 8 pin. I Think i'll try Powerlink.
 

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You have to run stress test if you want it know the situation is PSU / power related.

If you have GB3 paid version, there is a stress test for CPU. Or, there quite a few others free benchmarks / CPU stress test available, you can even use the YES command in terminal to do it.

ON TOP OF THAT, running Furmark GPU stress AT THE SAME TIME. Let it run at least 15min. Then you will know if that’s power related.

N.B. Do that with your normal config (e.g. back to dual mini 6pin to single 8)
 
This morning I turned on the Mac Pro and in the computer room the air conditioning was switched off. I think there is also the low voltage in my house.
The machine turns off immediately after logging in. 3 times i tried to run it, but after 1 or 2 minutes it shoutdown.
 
PSU should regulate the voltage. Boot into a live Linux distro if you can. No issues while doing AHT but shutdown in MacOS makes me think something is wrong with the OS. You can also try to install MacOS again, if you have a spare drive, just for testing.

Your GPU uses a small amount of power when idle, but a lot when active. If you have another GPU, swap and test please.

This morning I turned on the Mac Pro and in the computer room the air conditioning was switched off. I think there is also the low voltage in my house.
The machine turns off immediately after logging in. 3 times i tried to run it, but after 1 or 2 minutes it shoutdown.
 
PSU should regulate the voltage. Boot into a live Linux distro if you can. No issues while doing AHT but shutdown in MacOS makes me think something is wrong with the OS.

Well, when I had similar problems, it would pass AHT just fine with no errors reported with PSU. Apple got the same clean bill of health with their diagnostic tools in regards to PSU so that’s why they never suspected it and never replaced it.

This goes to show that these diagnostic tools are not always accurate and can’t detect absolutely everything that could possibly be faulty in a computer system.
 
I would start by removing everything but 1 drive to boot from including any optical drives you have. Lowest RAM config you can have and if you have one handy another video card. Preferably one that is basic as you can get, like a stock low end GPU. If you have anything plugged into the USB ports other than a mouse and keyboard I would unplug them as well. See if your machine comes up ok and stays running. Also I would get a UPS Battery backup one with a display on it that shows you incoming voltage and such. It will level out your power and ensure a steady voltage, it will also show you what voltage is being input to it from your house. If it still fails then I would suspect your PSU is bad. Also I would load something like this program https://sourceforge.net/projects/hwsensors/. This will not only show you temps but also voltage from the PSU. It sounds like you have something that is shutting down the PSU. It could be the PSU itself or the video card. I would suspect something that draws a lot of power. Here is a link to the repair manual for your MacPro. http://tim.id.au/laptops/apple/macpro/macpro_mid2010.pdf. In the manual it gives you step by step on troubleshooting this very issue. It's a lengthy procedure but hopefully will lead you to the culprit.
 
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Well, when I had similar problems, it would pass AHT just fine with no errors reported with PSU. Apple got the same clean bill of health with their diagnostic tools in regards to PSU so that’s why they never suspected it and never replaced it.

This goes to show that these diagnostic tools are not always accurate and can’t detect absolutely everything that could possibly be faulty in a computer system.
I've never been a fan of AHT. I had a laptop with a known issue and it passed 24 hours worth of AHT diagnosis. It may catch the basics but I wouldn't rely on it.
 
I had a 2010 iMac 27 that passed AHT all day but the video card was failing and never caught it. I would just follow the steps in the service manual I posted and start from there. Be patient and methodical and don't skip any steps. Personally I suspect the video card or many the backplane board as going bad. Sounds like you are losing one of the voltages and my bet is on the 5v.
 
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Update: I tried to power the GTX 780 with the Evga Powerlink without success. And a few days ago i replace my Gpu with a flashed GTX 680. During Heaven benchmark the Mac Pro turn off.
I don't know if it is a coincidence, but when the temperature in the room was less than 27 degrees (celsius) my Mac Pro seems work regulary.
With istat the voltage are regulary, but now i think i should try to replace PSU... What do you think?
Thank you.
 
Update: I tried to power the GTX 780 with the Evga Powerlink without success. And a few days ago i replace my Gpu with a flashed GTX 680. During Heaven benchmark the Mac Pro turn off.
I don't know if it is a coincidence, but when the temperature in the room was less than 27 degrees (celsius) my Mac Pro seems work regulary.
With istat the voltage are regulary, but now i think i should try to replace PSU... What do you think?
Thank you.

Sorry to hear that. To me it really sounds like your PSU is dying. With Electronics it is sometimes tricky compared to mechanical issues. Often there are electrical parts that experience a rather slow death over time. Capacitors and resistors can change their electrical value and go through a kind of aging process. Once that happens, symptoms like yours occurs. Inside the PSU are multiple stages for all kind of voltages, so one stage might go bad or can't stand a full load once graphic power draws more energy. I have seen posts here on macrumors recently that experience the same issues with advice where to get a new PSU. It should not be too expensive. Good luck to you
 
Sorry to hear that. To me it really sounds like your PSU is dying. With Electronics it is sometimes tricky compared to mechanical issues. Often there are electrical parts that experience a rather slow death over time. Capacitors and resistors can change their electrical value and go through a kind of aging process. Once that happens, symptoms like yours occurs. Inside the PSU are multiple stages for all kind of voltages, so one stage might go bad or can't stand a full load once graphic power draws more energy. I have seen posts here on macrumors recently that experience the same issues with advice where to get a new PSU. It should not be too expensive. Good luck to you
Hi,
now i'm waiting for new (refurbished) PSU, so i hope to solve the problem.
If i read in Terminal the shutdown cause it tells me: cause = 0 Power disconnected.
 
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Yes, most likely your PSU is dying!
44-45C is too hot when your not doing anything that stresses your Mac.
btw 37c Ambient is very high too....possible there is a lot of dust inside your PSU.
But from experience a PSU that runs 44/45c , on idle, will not recover from cleaning.

Buying a used PSU mostly guarantees you get one that also reads too hot, so check that you can return it!

PS, I test a PSU on cold boot with standard Ambient, like 20-28c...a healthy PSU should read 25/25c after cold boot.
 
Yes, most likely your PSU is dying!
44-45C is too hot when your not doing anything that stresses your Mac.
btw 37c Ambient is very high too....possible there is a lot of dust inside your PSU.
But from experience a PSU that runs 44/45c , on idle, will not recover from cleaning.

Buying a used PSU mostly guarantees you get one that also reads too hot, so check that you can return it!

PS, I test a PSU on cold boot with standard Ambient, like 20-28c...a healthy PSU should read 25/25c after cold boot.

I live in hot Asia, my computer temperatures may be more closer to OP's. With 34C ambient (very dust free, clean cMP), The PSU roughly run at 42C.

So, if his ambient it 37C, then 45C idle is very normal indeed. Of course, he can spin up the fan to cool down the PSU a bit.

For GPU temperature vs life span, this is a good thread to study.

https://forums.macrumors.com/thread...when-using-pc-non-efi-graphics-cards.1946672/
 
Hi!
On sunday I replaced the PSU of my Mac Pro. It is very simple.
Now the computer has been running for 3 days and i hope i solved the problem.
I would have 2 questions to ask you:

Where is the relay that you hear when you turn off the computer?
I noticed a strange thing happening before i replaced the PSU: when I regularly turned off the computer the led located on the ethernet switch (Dlink) sometimes turned off, sometimes not, is it normal?
Thank you very much for the advice.
 
Hi!
On sunday I replaced the PSU of my Mac Pro. It is very simple.
Now the computer has been running for 3 days and i hope i solved the problem.
I would have 2 questions to ask you:

Where is the relay that you hear when you turn off the computer?
I noticed a strange thing happening before i replaced the PSU: when I regularly turned off the computer the led located on the ethernet switch (Dlink) sometimes turned off, sometimes not, is it normal?
Thank you very much for the advice.
The relay is on the PSU.
 
My machine shuts down in the middle of the GB test. I only have Sonnet Pro PCIE adapter and the connector for my expansion chassis in slot 1. Tee video card is on the expansion chassis with 1500W platinum PSU inside, so the power draw inside the MAC should be minimal. I wonder if this is the PSU failing (again). This is my second replacement.
 
My machine shuts down in the middle of the GB test. I only have Sonnet Pro PCIE adapter and the connector for my expansion chassis in slot 1. Tee video card is on the expansion chassis with 1500W platinum PSU inside, so the power draw inside the MAC should be minimal. I wonder if this is the PSU failing (again). This is my second replacement.

Can you elaborate on the expansion chassis you currently use? Is it a Cubix Expander or more something like a Netster Turbobox with PCIe host adapter? Where are those GPU's located at the moment, which slot? You may want to avoid using AMD & Nvidia in one and the same cMP 5.1. Usually it can not handle two different GPU drivers. Does the Windows side crash as well, (if you have bootcamp or other systems in place)
 
Can you elaborate on the expansion chassis you currently use? Is it a Cubix Expander or more something like a Netster Turbobox with PCIe host adapter? Where are those GPU's located at the moment, which slot? You may want to avoid using AMD & Nvidia in one and the same cMP 5.1. Usually it can not handle two different GPU drivers. Does the Windows side crash as well, (if you have bootcamp or other systems in place)
No there is one RX-480 and some USB pcie card and 2 NVME's in there. It is a Cyclone PCIe2-2707 board. But I was reading on the net someone had similar issue and found one of his CPU's was failed (weird?). I may try same test under Windows to see if it is a hardware or software related and maybe try one CPU at a time.
 
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