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militantm1nd

macrumors newbie
Original poster
Sep 6, 2012
8
2
On a soundwave in Canada
Hi,

I am on a cMP 5,1: 12x3.33/64gb/GTX 980ti 6gb running OSX 10.12.6

If I choose startup disk to Win7, I boot to Win7. However I get stuck there and cannot get back into OSX. Choosing startup disk from Win7 does not work, neither does the restart in OSX option. My OSX drive disappears and cannot be seen (which was the case previously) from Win7.

Obviously I have no boot screen. I will either get a No bootable device text message, or just a reboot into Win7 from Win7. It literally takes me to rip out the GPU, replace with EFI 680, remove OSX hdd and reseat in different SATA slot, remove Win7 hdd and hold OPTION to see the OSX drive.

So clearly this is a really odd issue. I had no problems with earlier versions of Sierra with startup disk boot selection. Any insight and ideas would be greatly appreciated.

Thanks for the time and consideration!
 
Hi,

I am on a cMP 5,1: 12x3.33/64gb/GTX 980ti 6gb running OSX 10.12.6

If I choose startup disk to Win7, I boot to Win7. However I get stuck there and cannot get back into OSX. Choosing startup disk from Win7 does not work, neither does the restart in OSX option. My OSX drive disappears and cannot be seen (which was the case previously) from Win7.

Obviously I have no boot screen. I will either get a No bootable device text message, or just a reboot into Win7 from Win7. It literally takes me to rip out the GPU, replace with EFI 680, remove OSX hdd and reseat in different SATA slot, remove Win7 hdd and hold OPTION to see the OSX drive.

So clearly this is a really odd issue. I had no problems with earlier versions of Sierra with startup disk boot selection. Any insight and ideas would be greatly appreciated.

Thanks for the time and consideration!


Here's what I do... (Running 2 unflashed 1080 TI's - macOS HS APFS on it's own drive & Win 10 Pro on it's own drive)

0. This works.....

1. Disable SIP

2. Keep your macOS set as startup drive.

2. Install BootChamp (free) ---> https://www.kainjow.com/

3. Use BootChamp to boot to Windows. (It doesn't change your startup drive, only a one shot boot to Windows)

4. To get back to macOS from Windows just do a Restart from Windows and it will boot back to your macOS drive.
 
Last edited:
odd problem, the bootcamp drivers are correctly installed? may be worth trying to reinstall them.

you can always do a smc reset to get back to osx (or was it pram reset to get back to osx?)
to skip swapping GPU's

it's been a problem on osx10.13 that the file system apple has moved to can not be seen by windows but on 10.12 thats not a problem.

your booting from one of the sata ports i gess and not a copy of osx on a pci card?
 
Hi,

I am on a cMP 5,1: 12x3.33/64gb/GTX 980ti 6gb running OSX 10.12.6

If I choose startup disk to Win7, I boot to Win7. However I get stuck there and cannot get back into OSX. Choosing startup disk from Win7 does not work, neither does the restart in OSX option. My OSX drive disappears and cannot be seen (which was the case previously) from Win7.

I had the same issue with Windows 10. In my case, the Boot Camp control panel wasn't installed, and I couldn't switch to MacOS from within Windows.

My solution: I used Windows Command Prompt to install Boot Camp v. 6, which installed the drivers and Boot Camp Control Panel for Windows 10.

Check out the updated note to post #5 in this thread: Mac Pro Bootcamp help

YMMV, as I was dealing with HS 10.13.4 and Windows 10.
 
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I figured this out. What happens is that Windows sets itself as the boot priority during install. Download easyuefi and you can see this to be true. So regardless of what you set in OS X or whatever it always is boot 1 so windows boots up. Easyuefi can be used to change the boot order or to set one time boots for any of your volumes on the following restart. Whatever OS X does to bless the volumes in the startup disk selection pref pane results in a no bootable device error. However bootchamp is capable of booting up into windows from OS X.
 
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odd problem, the bootcamp drivers are correctly installed? may be worth trying to reinstall them.

you can always do a smc reset to get back to osx (or was it pram reset to get back to osx?)
to skip swapping GPU's

it's been a problem on osx10.13 that the file system apple has moved to can not be seen by windows but on 10.12 thats not a problem.

your booting from one of the sata ports i gess and not a copy of osx on a pci card?

Should be PRAM reset.
 
  • Like
Reactions: orph
Here's what I do... (Running 2 unflashed 1080 TI's - macOS HS APFS on it's own drive & Win 10 Pro on it's own drive)

0. This works.....

1. Disable SIP

2. Keep your macOS set as startup drive.

2. Install BootChamp (free) ---> https://www.kainjow.com/

3. Use BootChamp to boot to Windows. (It doesn't change your startup drive, only a one shot boot to Windows)

4. To get back to macOS from Windows just do a Restart from Windows and it will boot back to your macOS drive.

You sir have saved extreme pain and suffering on a disabled man's back. Thank you!
 
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