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HC on a true stock 4,1
- Thread starter adam9c1
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You mean High Sierra HS. I installed it on a HD but I have SSDs too in this Mac Pro and I needed to update the firmware. It went well with the stock GT 120. You need a bootscreen.
I guess Mac Hammer Fan already gave you the answer. (If your HC means High Sierra, and your 4,1 means Mac Pro 4,1, but not MacBook Pro 4,1, or Mac mini 4,1, etc.)
So how did you install 10.13 on a cMP 4,1 without the 5,1 flash?
Or what other firmware do you need to update?
Or what other firmware do you need to update?
You need to do the 5,1 firmware update first. This will allow you to run the High Sierra installer natively.
When you run the High Sierra installer, that will further update your firmware. This update allow your Mac to boot from the APFS partition.
After all these update, your cMP no will able to run High Sierra natively.
P.S. Mac EFI GPU is a requirement for any firmware flashing / upgrade.
So, to be really clear for me.... I have a Mac Pro 4,1 (El Capitan) with the firmware flashed to 5,1. When I upgrade to HS, the "additional firmware" upgrade won't roll me back or screw up my 5,1 flash?
Thanks.
Thanks.
I have been experimenting with this for some time and would like to offer some input and request anything that anyone else finds out.
For myself, I am looking to be able to restore or image HS as it is no longer supported with APFS unless a device is already on HS. I have repacked the firmware updater .pkg from the official HS installer, ran it on a SUPPORTED machine and noticed that it only in my case changed the boot ROM.
I was able to use AutoDMG to create a HS asr image, restore it using the HS installer from terminal, mount the Macintosh HD partition and target it with the installer function to install firmware. The next reboot will be long as firmware goes from EFI partition to Boot ROM, but the device boots and otherwise functions normally. I couldn't see that the installer changed anything else.
I would assume that for what this thread is trying to accomplish, using the appropriate firmware you could flash it while running regular Sierra, reboot, the asr restore HS to the machine in question.
If anyone attempts this and finds that after officially running the install that more firmware is updated elsewhere please post here.
For myself, I am looking to be able to restore or image HS as it is no longer supported with APFS unless a device is already on HS. I have repacked the firmware updater .pkg from the official HS installer, ran it on a SUPPORTED machine and noticed that it only in my case changed the boot ROM.
I was able to use AutoDMG to create a HS asr image, restore it using the HS installer from terminal, mount the Macintosh HD partition and target it with the installer function to install firmware. The next reboot will be long as firmware goes from EFI partition to Boot ROM, but the device boots and otherwise functions normally. I couldn't see that the installer changed anything else.
I would assume that for what this thread is trying to accomplish, using the appropriate firmware you could flash it while running regular Sierra, reboot, the asr restore HS to the machine in question.
If anyone attempts this and finds that after officially running the install that more firmware is updated elsewhere please post here.
The additional firmware upgrade will simply add APFS boot ability to your 5,1. That's it.
And your Mac Pro is a 5,1 now. It will react and perform identical as a real 5,1. It won't roll back, and cannot roll back by itself.