SOLVED Mac Pro 6.1 A1481 (2013) Cylinder Mac

[roskruge]

The computer will 'Shutdown' when requested will Startup by a slight press of the On button. but the computer will not do an automatic 'RESTART' like when you do system updates. The on button light comes on for a few seconds, then she just crashes. In other words, she tries to do a restart but cannot make the grade.
What is the source of the problem ?
D300 - 1 x 32GB Ram - 500 GB SSD - 2.7 Ghz 12 core - OS 10.14.6 - Purchased April 2014

 

[Cory Cooper]

Hello and welcome.

From your description, it looks like the original Apple RAM has been replaced with a single 32 GB third-party stick. The Mac Pro does use memory interleaving, so it is best to install RAM in matched pairs. If you still have them, I would try removing the third-party RAM and installing the Apple RAM.

I have seen the issue you are having caused by OS issues, especially when it starts after an incremental OS or security update. A reinstall over the top of the current Mojave install can sometimes fix it. Of course, it is always best to have a current Time Machine or other backup of your data.

You could also try to install mcOS Mojave on an external drive, startup from it, and see if the issue persists. If not, then it is probably an OS issue. If it does, then it would be more of a hardware issue.

C

 

[roskruge]

Thanks very much for your helpful comments - still have the 3 x 4GB plus 1 x 4GB from Apple

 

[Cory Cooper]

No worries...

Let us know how it goes, and we'll be happy to troubleshoot from there.

C

 

[roskruge]

Mix and matched with another Mac Pro- the problem was not RAM or my corrupt OS. I think the problem was more than likely a fault in the I/O Wall. I cannibalise old Mac Pro's (late 2013) so come up with numerous Hardware & Sofware problems.

 

[Cory Cooper]

OK, thanks.

C