Mac Pro 2012 random shutdown

Question

Level 1

8 points

Mac Pro 2012 random shutdown

I recently purchased a Mac Pro 2012 server single 4 core CPU. It’s begun to shutdown randomly as if the power cord has been pulled. It not an heat issue either. I thought I had it solved but today it started, after a system update.

Upgrades

computer came as purchased. 500gb hard drive and 4gb of RAM. Even the OS was what it shipped with.
Upgraded to HighSierra
Applied firmware upgrade
upgraded video card
installed 32gb of RAM
installed USB 3 card / mSata PCIe card / NVME PCIe card
Upgraded to Mojave

After a few weeks after everything was installed and running the shutdowns started and became more frequent. I was assuming it was the power supply. At that time I decided to try to eliminate the cause by tearing the computer down and adding one thing at a time back until I found the issue. After I inspected the motherboard and CPU card I ran the test.

I started with just the motherboard and let it run. Then I added one component at a time and let it run 30 minutes each time. Eventually it was put back together and just kept running until today.

Today the issue started again. I started by pulling PCIe cards to see if there was an issue and discovered if it runs without a boot drive it will stay on. I tried an external with Mojave and it and had the same problem.

As long as there is no OS to boot it stays powered on. What could possibly be the issue?

Mac Pro

Posted on Oct 10, 2019 9:42 PM

Reply

Answer 1

Top-ranking reply

Geotrax

Level 3

568 points

Oct 28, 2019 11:59 AM in response to brentfuchs

Hello brentfuchs! I apologize for the late reply.

In my experience with my own 2012 Mac Pro, random shutdowns that are like somebody is pulling the plug are caused by power supply or power delivery issues.

What video card are you using?

For me, random shutdowns were caused when I was using a Single 6-pin to Single-8pin adapter with my RX 590, which resulted in shutdowns when the system encountered heavy graphics load.

Can you tell us what your upgraded video card is, and how you are powering it? (Maybe a picture?)

I hope this helps!

-Geotrax

Reply

Answer 2

brentfuchs Author

Level 1

8 points

Oct 28, 2019 1:06 PM in response to Geotrax

Thanks for the reply.

I got a copy of Apple's technician's guide, or whatever they call it, and ran through the step by step diagnostic test. Several hours later I had it all back together and had not reached a conclusion. All test passed. I concluded it had to be the power supply. After installing a new one there was an instant change. The time from power on to chime decreased and after spending so much time I could tell the fans were putting in a little more effort. It's literally been running since.

I'm running a GTX 680 2GB that was gifted to me. I was waiting on the power issue to be resolved before upgrading the graphics card. It has two 6 pin connections and everything is running fine. I'm planning on a RX580 8GB for the upgrade. DO you plug both connections in or just the 8 pin?

Reply

Answer 3

Geotrax

Level 3

568 points

Oct 28, 2019 5:13 PM in response to brentfuchs

Hey brentfuchs!

Which RX 580 are you going to use?

On the RX 580, the card variants such as the Sapphire's Nitro+ and the ASUS Strix cards will have an 8 pin AND a 6 pin. This is to support overclocking in PC scenarios, but in this case, the 6 pin is optional.

8 pin provides more wattage than a 6 pin, so generally, you need to convert two 6 pins to get an 8 pin.

This adapter should work, and is what I am using with my Sapphire RX 590.

Hope it helps!

-Geotrax

Reply

Answer 4

brentfuchs Author

Level 1

8 points

Oct 29, 2019 6:52 AM in response to Geotrax

I haven’t ordered yet but I’m leaning towards the XFX RX580 8GB. There are different “editions” that all seem very similar but from what I’ve read the black edition performs well.

Reply

Answer 5

Geotrax

Level 3

568 points

Oct 30, 2019 11:43 AM in response to brentfuchs

That should be a good choice. Let us know how it works out!

Reply

Mac Pro 2012 random shutdown

Similar questions