mksCH wrote:
When i boot the Mac using Option + D (or only D as stated on the Apple Website), the Mac boots normally to the UI.
Make sure to use a wired Keyboard so you can access the special startup keys since wireless keyboards do not go ready soon enough to register the special keys. The keys must also be held down within a second or two of hearing the startup chime. If you hold them before the chime, then they may not be recognized either (sometimes this is system dependent).
Do you have a firmware password lock enabled? If so, then it will ignore the startup keys for the Apple Diagnostics. Temporarily disable the firmware lock so the special startup keys can be used. You can confirm whether you have a firmware password lock enabled by Option Booting by holding down the Option key to see whether you see a padlock icon.
One of the 4 4GB Memory's is just not available any more. The machine runs with 12 GB.
Far more a problem are the frequent hick up's when copying and saving data on the internal SSD. I probably have to replace the SSD, but before, I want proof for this. Therefore I want to run the diagnostics.
macOS 10.15+ has a lot more security features these days which can affect being able to save or even access files in certain areas. Third party apps and even some macOS apps must be give explicit permission to access some areas of your home user folder or even external media. Plus users should now only be storing files within their own home user folder or within the "Shared" folder in "/Users/Shared".
If you want to check the health of the SSD, run DriveDx and post the complete text report here using the "Additional Text" icon which looks like a piece of paper. Unfortunately the Apple SSDs don't provide much in the way of health information, but it never hurts to check. Plus not all "Warning" or "Failing" notices mean an SSD is bad so the SSD's health report needs to be manually examined & interpreted.
Unfortunately there are no real good ways of verifying the health of an SSD...examining the SSD's health report is the best option available. From supporting thousands of computers for our organization, most SSD failures are due to the SSD's controller failing which has no way of being tested and those failures tend to be quite sudden with little to no warning signs.
The Apple Diagnostics are just a basic diagnostic mainly checking for the presence of various components and sensors. The memory and GPU test are the most involved of the tests outside of the sensor checks and even they are quite limited in scope (Memtest86 is a much better test as it can be run for hours or even days). There are usually other better ways to test hardware if needed by running an app focused on the particular bit of hardware.
There is a slim chance the memory module may just need to be reseated (make sure the Mac is unplugged first). Since it is completely missing, I personally would want to identify which module/slot it is which may require removing one module at a time and powering on the Mac to see if the memory changed.
It doesn't make any sense to run any memory tests until the bad memory or memory slot is identified and taken out of the picture. You can use a bootable Memtest86 USB stick to test the memory. I've been finding that if the default Memtest86 options don't detect a problem, that you should change the Memtest86 CPU settings to "Round Robin" or "Sequential" which I've been finding tends to detect issues better (may result in a frozen test instead of an error, but still useful none the less).
To look for possible software issues you can run EtreCheck and post the complete text report here using the "Additional Text" icon which looks like a piece of paper.
macOS 12.6.1 is the last version available for my Mac Pro 2013!
Ooops! I think the "IO" in iOS made me see it as 10.12 instead of 12.6.1. Sorry about that and thanks for pointing out my mistake.
