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OSX Downgrade Issue/Boot Drive

T

tobiasenstrom

macrumors newbie
Original poster
Mar 30, 2018
24
3
I'm downgrading from High Sierra which was shipped with the Mac, to Sierra without using Time Machine and get stuck at the restart stage.

I've created the boot drive USB using terminal and Install Disc Creator but the process falls down every time I restart the Mac.

I restart the Mac while holding the alt/option key and I'm meant to get the option to choose bootable install drive but I just get a black screen and nothing happens.

I have also tried the alt+cmd+r+p which has not made a difference

I have followed the instructions from here:

and from here: https://setapp.com/how-to/downgrade-from-macos

Am I missing something?

Thanks
 
tobiasenstrom said:
I'm downgrading from High Sierra which was shipped with the Mac, to Sierra without using Time Machine and get stuck at the restart stage.

I've created the boot drive USB using terminal and Install Disc Creator but the process falls down every time I restart the Mac.

I restart the Mac while holding the alt/option key and I'm meant to get the option to choose bootable install drive but I just get a black screen and nothing happens.

I have also tried the alt+cmd+r+p which has not made a difference

I have followed the instructions from here:

and from here: https://setapp.com/how-to/downgrade-from-macos

Am I missing something?

Thanks
Click to expand...
What's your Mac? Year and model, please.
 
Probably your GPU doesn't have a Mac boot ROM? What graphics card are you running? This would prevent you seeing the bootpicker screen when holding option... Without knowing what GPU you have it's hard to know for sure.
 
Ok, let me do this properly.

Mac Pro 5.1 mid 2012
10.13.6
2x 3.46 Ghz 6 Core
96GB
Radeon RX 570 4GB
currently have 3 monitors hooked up and all are black when doing the restart

I get the normal boot up screen but it does take a while to show
 
tobiasenstrom said:
Ok, let me do this properly.

Mac Pro 5.1 mid 2012
10.13.6
2x 3.46 Ghz 6 Core
96GB
Radeon RX 570 4GB
currently have 3 monitors hooked up and all are black when doing the restart

I get the normal boot up screen but it does take a while to show
Click to expand...
With no Mac EFI GPUs/PC GPUs, like RX 570, you have to remove all disks, insert the createinstallmedia USB key and an empty/erased drive. After that, your Mac Pro will boot from the createinstallmedia USB key and you can install Sierra on the empty drive.
 
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tobiasenstrom said:
Ok, let me do this properly.

Mac Pro 5.1 mid 2012
10.13.6
2x 3.46 Ghz 6 Core
96GB
Radeon RX 570 4GB
currently have 3 monitors hooked up and all are black when doing the restart

I get the normal boot up screen but it does take a while to show
Click to expand...

Yep, doesn't have a boot rom. You'll need a real Mac video card. Unfortunately even a used Mac Pro version of a lowly Radeon 2600XT isn't that cheap ~$60.
 
Thanks tsialex.

As you can tell from my previous posts, you can tell I'm not the sharpest tool in the box so I will repeat it back to make sure I understand what you're saying.

I put a blank drive in the Mac
place usb in Mac
switch it on
Mac will load from usb
I then install Sierra on blank drive
restart computer minus usb and it will load in Sierra
 
tobiasenstrom said:
Thanks tsialex.

As you can tell from my previous posts, you can tell I'm not the sharpest tool in the box so I will repeat it back to make sure I understand what you're saying.

I put a blank drive in the Mac
place usb in Mac
switch it on
Mac will load from usb
I then install Sierra on blank drive
restart computer minus usb and it will load in Sierra
Click to expand...
Correct. With just the createinstallmedia USB key and an empty drive, Mac Pro will boot from the createinstallmedia USB key. After the install, you shutdown and remove the createinstallmedia USB key.
 
Thank you all for your assistance.

As always when ever I ask my daft questions on here I always get help and no flaming involved.

Have a good weekend y'all!
 
Ok, it's still not working.

  • I've downloaded Sierra
  • Run terminal to create install media on USB drive
  • Have inserted a brand new blank hard disc which is formatted as Mac OS Extended (Journaled) and GUID Partition Map
  • I have removed the original bootable drive so the only drive is the new one
  • The USB is in the Mac
  • I start the Mac
  • Nothing happens: The screen is still in standby mode, the white light on the Mac is lit, the light on the USB drive is not blinking.
  • I leave it for 5 mins. No change
  • I push the power button on the Mac and it switches off instantly. When I push the power button as I type this, nothing happens.
Stupid Question: Does it matter that the new drive in slot 2 and not slot 1?

Is this related to not having the boot screen?

I have the graphics card from my early 2008 model. Can I put that in the new Mac and get the boot screen so I can install Sierra and then put the new graphics card back in the new Mac?
 
tobiasenstrom said:
Stupid Question: Does it matter that the new drive in slot 2 and not slot 1?
Click to expand...
No.

Is this related to not having the boot screen?
Click to expand...
Can be, if you didn't erased correctly your drive and your Mac Pro is trying to boot from it or your createinstallmedia USB install is not working correctly. Some USB keys don't work correctly for Mac Pro boot, I have some Kingston that just don't work, did you try another model? Use a native USB2.0 port.

I have the graphics card from my early 2008 model. Can I put that in the new Mac and get the boot screen so I can install Sierra and then put the new graphics card back in the new Mac?
Click to expand...
Any original Apple GPU or Mac Edition card, from early-2008 to mid-2012 will work.
 
Thanks tsialex.

This is what I put in terminal: sudo /Applications/Install\ macOS\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/Sierra --applicationpath /Applications/Install\ macOS\ Sierra.app

Terminal confirmed it completed ok.

I will try the graphics card from the other Mac this weekend and report back what happens.
 
tobiasenstrom said:
Thanks tsialex.

This is what I put in terminal: sudo /Applications/Install\ macOS\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/Sierra --applicationpath /Applications/Install\ macOS\ Sierra.app

Terminal confirmed it completed ok.

I will try the graphics card from the other Mac this weekend and report back what happens.
Click to expand...
You used the correct command if you formatted your USB key as Sierra. Try with another USB key, some just don't work. Btw, only the Mac Pro native USB2.0 ports works for boot.
 
I'm using the usb slots on the front of the Mac.

I'll try another USB key, that's less hassle than swapping out the graphics.
 
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