Mac Pro 5,1 fails to boot after recent update

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Level 1

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Mac Pro 5,1 fails to boot after recent update

There are similar problems reported earlier but none of the proposed solutions yield any results for me. What happened was that I updated the system from dialog as you normally do when system updates are released. How ever my computer never booted up. I had non standard graphics card that does not have Apple BIOS (Radeon rx580) but this have never before given any problems other than not seeing the apple logo and initial pre-os boot progress bar. This time login screen never came up. So I went and bought old apple original graphics card. What happens is that progress bar goes all the way ready but login screen does not appear. What I have tried so far is:

I have tried to safe booting and to get to recovery tools (cmd-r and alt-cmd-r-p and so on)but with out success.
remove power cord for awhile and boot, no success
remove coin battery from mother board for while NVRAM, no success
took out all hard drives and insert blank HD, no success not even the progress bar.

I am a bit ****** that system update seem to have completely broken my computer. I have USB -keyboard but I am not sure if that is working OK on the boot because if I press caps lock, LED wont turn on while trying to boot (I am not sure if it should). If I remove all hard drives I get the folder icon and then caps lock work so keyboard is detected at some point of the boot.

Is there anything else I could try to bring this computer to life?

Mac Pro, macOS 10.14

Posted on Aug 23, 2021 3:04 AM

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Answer 1

Best reply

Grant Bennet-Alder

Level 10

127,135 points

Aug 23, 2021 9:13 AM in response to kkolehma

Mac Pro 5,1 does not have Internet Recovery in its ROM.

You need a different stand-alone recovery partition somewhere. If the one on the boot drive is not working, you could use one of these:

• an appropriate 10.6 Installer DVD

• a different bootable macOS drive, internal or external

• a bootable Installer USB-stick -- a little hard to make now if you don't already have one on hand.

--NB> you can use its Utilities and NOT re-install

• a Time machine backup drive after 10.7.3

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Answer 2

Aug 23, 2021 7:23 AM in response to kkolehma

Diagnosis: bad blocks on the Boot Drive.

--------

The initial "chime" sound is generated in software when your Mac passes the Power-On Self Test. If the chime occurs and/or startup continues, your Mac is working. The blank gray screen should light up. Then on to the disk Drive.

Accessing the Boot drive:

The solid Apple is not in the Mac's ROM at Cold start. The Apple logo can only appear when it is fetched in the first "blob" of software loaded from a 'magic' place on the boot drive, or re-run after a Restart. Then a whole lot of stuff is initialized, and the progress Bar moves part way across. After a cold start, seeing the solid Apple appear says your drive is not completely dead.

Mounting the Boot drive:

The next step requires a lot of files by name, so the File System is initialized, and the Boot Drive is Mounted. If the drive directory is damaged, the drive can not be Mounted, so your Mac begins one pass of Disk Utility Repair. This will take an additional about five minutes. During this process, the progress bar may be extended, and will grow by an additional amount not seen on a routine startup.

at the end of that process (which should not take more than about five minutes), it will attempt to Mount the drive again:

-- if the drive Mounts, boot-up continues.

-- if the drive cannot be Mounted, your Mac can do nothing more, so it powers off.

-- if the process stalls, this may indicate you have Bad Blocks on your Rotating Magnetic Boot drive (if so equipped). The re-reading of Bad blocks can take a very long time (on the order of a quarter minute for each Bad Block).

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Answer 3

kkolehma Author

Level 1

10 points

Aug 23, 2021 8:11 AM in response to Grant Bennet-Alder

Thanks for the answer. I tried once leave it over night but it did not progress. Still I would think that that the cmd-r or other combinations would force it to boot recovery mode and access disk utility. Or that keyboard LED for caps lock would show some life, but no...

Progress bar gets awfully slow towards the end so bad blocks sounds plausible explanation. I will have to refresh my memory on how to make install medium to USB stick and try fresh install. Can it be that recovery tools reside also on boot disk and if that is bust, those are inaccessible as well? I thought that at least network recovery option would be useable without working boot disk located in some flash memory or something but I suppose that is not the case.

PS. boot drive is Samsung evo 850 SSD, but SSD is certainly not immune for failure

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Answer 4

kkolehma Author

Level 1

10 points

Aug 23, 2021 8:55 AM in response to kkolehma

Seems I have to fall back al the way to Sierra because it seems you can not download for example Mojave with M1 MackBook Pro from App Store... That is one shortcoming of "App Store only" download for restoring older Mac that does not support Big Sur.

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Mac Pro 5,1 fails to boot after recent update

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