2013 iMac - NVMe upgrade issues

[ArchStudent]

Hello,


I recently installed a sinetech adapter and a 500gb Western Dogital Black NVMe drive in to my late 2013 21.5” iMac.


iMac specifications:


CPU - i7
RAM - 16 GB
GPU - 1GB Nvidia
500 GB WD black NVMe
1 TB 5400 rpm HDD
OSX - Mojave (fresh clean install and updated)

The physical install was easy (take your time and be patient) and also allowed me to clean out some well hidden dust bunnies!


Following the upgrade and fresh Mojave install, the system seems to eventually power off when left alone, and I have to turn it back on by physically pressing the power button (annoying).


It also does a double chime upon starting up.


Other than those two annoying issues, efficiency has increased significantly in my workflow!


Would someone be able to chime in on what solutions are out there?


Terminal code for the power off issue to stop?


Thanks

 

[barbu]

random shutting down sounds like a power supply problem to me. Unless you get a message when starting up about "an error has occurred" or similar, then that is something else. But if it's just switching off and when you turn it back on, it acts like nothing has happened, I would consider the PSU as a culprit.