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It's impossible to get Windows UEFI boot working on a MacPro1,1, right?
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Since no Apple MacPro system supports the industry standard UEFI, seems likely.
You're right, preliminary Windows EFI boot support began with Mac Pro 5,1 but it's still shoddy and has issues, to say the least.
It's possible to install Windows in UEFI mode, In Fact, I installed a week ago Windows 10 on my Mac Pro using a Sonnet Tempo SSD (That does not support BootCamp), in UEFI mode and works like a champion. 
For all the users using a Tempo SSD Card, Windows can be installed without any hack in UEFI mode, and works fine. Also can be used with BootCamp using Boot Manager (Available on my GitHub)
For all the users using a Tempo SSD Card, Windows can be installed without any hack in UEFI mode, and works fine. Also can be used with BootCamp using Boot Manager (Available on my GitHub)
I have a MacPro5,1 too and (after some effort) it seems to work fine to boot Windows 10 into UEFI on that, and it does seems to run a bit faster compared to how it ran when booted into legacy mode. What issues are you referring to?
But good to know there's no point in trying to get it to work in a MacPro1,1 — thanks.
It probably depends on your hardware configuration, but some people were having issues with certain SATA drive configurations and PCI cards not being recognized properly in Windows, but some were doing just fine. Mileage may vary.I have a MacPro5,1 too and (after some effort) it seems to work fine to boot Windows 10 into UEFI on that, and it does seems to run a bit faster compared to how it ran when booted into legacy mode. What issues are you referring to?
But good to know there's no point in trying to get it to work in a MacPro1,1 — thanks.
For all the users using a Tempo SSD Card, Windows can be installed without any hack in UEFI mode, and works fine. Also can be used with BootCamp using Boot Manager (Available on my GitHub)
May I ask how (because I guess it does?) Boot Manager handles the fact that the the EFI partition to boot Windows doesn't always have the same disk identifier between restarts (or whatever it is that makes that change)?
@abdyfranco I downloaded Boot Manager from the beautiful homepage at http://abdyfran.co/projects/boot-manager (Next Loader seems interesting and looks great too by the way) for use with my MacPro5,1 and it seemed to work well, but after installing the Windows 10 October 2018 Update (version 1809) and restarting because of that I got back into Windows again. No I can't seem to get back into MacOS again.
It's supposed to be a one time restart into the operating system selected in Boot Manager, right? Do you think my update to Windows 10 1809 messed things up? I can't use the startup manager (alt/option during boot) because I have a non-Mac-EFI GPU. I'd rather not open up and swap the GPU out to my Mac-EFI one for the hundredth time.
A PRAM reset still gets me into Windows. I don't understand why. Was thinking I could reset thePRAM NVRAM, get into MacOS with no video (since I have an NVIDIA 1070 GPU and resetting the PRAM NVRAM sets the driver back to to built-in) but since I have Remote Management enabled I should be able to remote control the Mac Pro from my portable Mac, which have worked before. And the problem is I can't easily remove the Windows 10 disk from the computer since I've tucked that drive into the area where the second optical drive can be installed. Hmm... Maybe just bite the bullet and swap out the GPU to the Mac-EFI one yet again...
It's supposed to be a one time restart into the operating system selected in Boot Manager, right? Do you think my update to Windows 10 1809 messed things up? I can't use the startup manager (alt/option during boot) because I have a non-Mac-EFI GPU. I'd rather not open up and swap the GPU out to my Mac-EFI one for the hundredth time.
A PRAM reset still gets me into Windows. I don't understand why. Was thinking I could reset the
Hmm... Maybe just bite the bullet and swap out the GPU to the Mac-EFI one yet again...
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Boot Manager only sets a boot drive as a one-time boot (--nextonly), so the next reboot should return to macOS, but today I have happened exactly the same as you and I received confirmation from 4 other users to confirm that the Windows update is the cause of the problem.@abdyfranco I downloaded Boot Manager from the beautiful homepage at http://abdyfran.co/projects/boot-manager (Next Loader seems interesting and looks great too by the way) for use with my MacPro5,1 and it seemed to work well, but after installing the Windows 10 October 2018 Update (version 1809) and restarting because of that I got back into Windows again. No I can't seem to get back into MacOS again.
It's supposed to be a one time restart into the operating system selected in Boot Manager, right? Do you think my update to Windows 10 1809 messed things up? I can't use the startup manager (alt/option during boot) because I have a non-Mac-EFI GPU. I'd rather not open up and swap the GPU out to my Mac-EFI one for the hundredth time.
A PRAM reset still gets me into Windows. I don't understand why. Was thinking I could reset the PRAM, get into MacOS with no video (since I have an NVIDIA 1070 GPU and resetting the PRAM sets the driver back to to built-in) but since I have Remote Management enabled I should be able to remote control the Mac Pro from my portable Mac, which have worked before. And the problem is I can't easily remove the Windows 10 disk from the computer since I've tucked that drive into the area where the second optical drive can be installed.
You can try to use the "Restart in OS X" option, This option should take you back to macOS in verbose mode, although there are reports that this doesn't work after the Windows update either (although it did work for me).
Apparently Windows updates rewrite part of the Mac's NVRAM, changing the boot disk to Windows. (Probably using the "bcdedit" command, equivalent to "bless" in Windows)
If resetting the PRAM/NVRAM does not work, the only alternative would be to install an EFI GPU, so you can use the Startup Manager and select macOS again. Unfortunately this is a problem with Windows that I can't fix in Boot Manager.
Thank you so much for the quick reply and information!
Great to know for future Windows updates. And really great work on the Boot Manager - I'd be happy to donate a little once I get it up and running (don't have time to contribute in any other ways at the moment).
By the way, if I could easily remove the drive where I have Windows 10 and just have the drive where MacOS is installed in the computer it should eventually boot into MacOS, right? If that works it might be the way to go next time I update Windows 10 (but first have to move the drive with Windows 10 to a more accessible drive slot...).
EFI Windows do a lot of weird things, like signing the BootROM multiple times. I found a BootROM with 2 Windows X509 signing certificates in the private part of the NVRAM.
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In theory, should work. The Mac will not be able to find the Windows drive and should fallback to macOS.Thank you so much for the quick reply and information!
Great to know for future Windows updates. And really great work on the Boot Manager - I'd be happy to donate a little once I get it up and running (don't have time to contribute in any other ways at the moment).
By the way, if I could easily remove the drive where I have Windows 10 and just have the drive where MacOS is installed in the computer it should eventually boot into MacOS, right? If that works it might be the way to go next time I update Windows 10 (but first have to move the drive with Windows 10 to a more accessible drive slot...).
Windows EFI is weird, In fact Boot Manager has two different codes for EFI handle, one only for Windows and another for macOS and Linux, because the Windows EFI works differently.
@abdyfranco ... after installing the Windows 10 October 2018 Update (version 1809) and restarting because of that I got back into Windows again. No I can't seem to get back into MacOS again.
It's supposed to be a one time restart into the operating system selected in Boot Manager, right? Do you think my update to Windows 10 1809 messed things up? I can't use the startup manager (alt/option during boot) because I have a non-Mac-EFI GPU. I'd rather not open up and swap the GPU out to my Mac-EFI one for the hundredth time.
A PRAM reset still gets me into Windows. I don't understand why. ....
Maybe just bite the bullet and swap out the GPU to the Mac-EFI one yet again...
I'm another victim of Win 10 v1809 yesterday. Same problem. But resetting PRAM does work for me. Are you sure you got it reset? Of course resetting PRAM is a terrible workaround because resetting PRAM fully re-enable SIP which prevents all methods (bless scripts, Boot Manager, etc) to boot into Windows from working. So once back in Mac OS after a PRAM reset you have to boot back into recovery mode to disable SIP-nvram again. YUCK!
Anyone know if Win 10 legacy BIOS installations were also hosed by v1809?
Before I realized it was the Win 10 update that caused the problem I tried a bunch of stuff to "fix" the problem and eventually messed everything up. So now I'm going to re-install Win 10. If I install UEFI boot, then I have to put my EFI video card back in my 2010 Mac Pro (yeah for the hundred and 1st time) because I've never found a way to boot my Win 10 installer DVD (made from Win iso) into the UEFI mode without a boot screen. Does anyone have a solution for that?
I wonder if I can install Win 10 with plist-modified BootCamp Assistant without boot screens? It's been years since I tried that so I don't remember. That would create legacy-BIOS boot, and I'm not sure that is a good idea with Win 10. I install to a separate 1 TB drive so I want an HFS volume on the drive too and I don't think Bootcamp assistant supports putting more than one volume on a separate drive. I guess I could put another install of 10.13 on it and then erase that later?
Anyone have thoughts on using Win 10 with legacy-BIOS vs UEFI?
Legacy installations does not have access to the NVRAM or EFI sector, so very likely will not present this problem.
So I should probably re-install legacy BIOS to prevent this from just happening again.
Now I have to remember how to get BIOS without boot screens. I know my Win 10 installer DVD boots into BIOS mode without the boot screen. But I'm not sure how to partition my hard drive into hybrid EFI/MBR without Boot camp assistant (which I just checked does not allow more than 1 partition on a separate drive). The Disk Utility produces a GUID GPT disk so that alone doesn't work.
A PRAM reset still gets me into Windows. I don't understand why. Was thinking I could reset the PRAM, get into MacOS with no video (since I have an NVIDIA 1070 GPU and resetting the PRAM sets the driver back to to built-in) but since I have Remote Management enabled I should be able to remote control the Mac Pro from my portable Mac, which have worked before. And the problem is I can't easily remove the Windows 10 disk from the computer since I've tucked that drive into the area where the second optical drive can be installed.
Are you certain you are resetting the NVRAM? With a successful NVRAM reset you should hear multiple startup "bongs", not just one.
In any case, you can install EasyUEFI onto Windows and use it to change the default boot (or just next boot) back to MacOS (or whatever else you want).
I figured out how to make a hybrid EFI/MBR drive to install Win 10 from my Installer DVD and still have an extra HFS partition.
I first used Disk Utility to create a separate HFS drive. I then loaded High Sierra on it just so I could use BootCamp Assistant to create a non-GPT drive to load Win 10. I'll erase HS later.
I could then use a plist-modded Bootcamp Assistant to create a 2nd partition on that drive for Win 10, and it allows resizing both partitions at the same time. But I had to first use BA to create an otherwise useless USB Win Installer stick just to access that option, because it did not recognize the Win 10 install DVD mounted on the desktop for that purpose.
I then bailed out BA and rebooted to the DVD Installer by holding down the C key. From there I was able to reinstall Win 10 as a legacy-BIOS boot without having any boot screen on my non-EFI video card (RX-560). At the point that the installer auto-restarts it jumps back to Mac OS. but then I could select the Win partition in Startup Disk preferences and reboot to Windows to complete the install.
I installed from a v1803 Win Installer so everything is now working. i.e. I can boot into Win 10 and then use the Bootcamp controller in Win 10 to reboot to the HFS version of High Sierra (not an APFS version).
I'll follow up by updating to v1809 which broke the EFI Boot Win 10, and see if the legacy-BIOS boot version of v1809 still works or is broken. More on that later.
Installed the Win 10 1809 update a couple of days ago and my "Nextonly" script works as it did before the upgrade.
No changes att all for me.
My Win 10 system is on a Samsung EVO 860 SSD in Bay 1 and Win is running in UEFI mode.
Mojave 10.14 (18A391) is on a Samsung EVO 850 SSD formatted in APFS and in the lower optical drive bay.
I also have a Mojave bootable backup on a Black WD 1TB HDD (HFS+ formatted) in Bay 2 so I never get stucked in Win since I can choose the Mojave backup disc in Win Bootcamp, however it will always start on the Mojave APFS SSD which is a good thing but I don't know why it behaves like this.
Setup:
Mojave 10.14
Mac Pro mid 2010
2x3,46 Ghz
24Gb RAM
Sapphire Radeon RX580 Pulse 8GB
Boot ROM Version: 138.0.0.0.0
No changes att all for me.
My Win 10 system is on a Samsung EVO 860 SSD in Bay 1 and Win is running in UEFI mode.
Mojave 10.14 (18A391) is on a Samsung EVO 850 SSD formatted in APFS and in the lower optical drive bay.
I also have a Mojave bootable backup on a Black WD 1TB HDD (HFS+ formatted) in Bay 2 so I never get stucked in Win since I can choose the Mojave backup disc in Win Bootcamp, however it will always start on the Mojave APFS SSD which is a good thing but I don't know why it behaves like this.
Setup:
Mojave 10.14
Mac Pro mid 2010
2x3,46 Ghz
24Gb RAM
Sapphire Radeon RX580 Pulse 8GB
Boot ROM Version: 138.0.0.0.0
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I'm quite certain, yes. The same procedure as resetting the older Mac computers' PRAM (sorry for mixing PRAM with NVRAM in my previous post) -- I hold down cmd, alt/option, P and R after restart and keep them down until I hear the startup chime a second time, which in my case yesterday meant the chime volume was increased since it went back to the default volume, which I take it should indicate the NVRAM reset was successful? But yeah, it's really strange that I don't get booted back into MacOS after a NVRAM reset. Don't think it has ever worked on this setup for me -- I always get booted into Windows regardless.
Hmm... Could it be because I have the Windows 10 drive in the SATA port that goes to the second optical drive bay and that the computer (after a NVRAM reset) thinks it should try booting from any optical drive before any other drives, which in my case has an SSD with Windows 10? But there should be no difference between the SATA ports in the computer in this regard, or?
Thank you for the info on EasyUEFI. Will take a look at it (see it costs quite a lot after trial has expired...)t. You don't think it will mess things up if I use Abdy's Boot Manager from within MacOS too?
Hmm... Interesting that updating Windows to 1809 worked for you. I wonder what is different with our setups.
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Didn't know it seems possible to disable SIP only for the NVRAM:
csrutil enable --without nvram
Seems better than disabling SIP entirely, doesn't it?
csrutil enable --without nvram
Seems better than disabling SIP entirely, doesn't it?
"EasyUEFI Free" is free for personal use.
I have no experience with Abdy's Boot Manager, so I don't know. But I can't see why they wouldn't coexist just fine.
I tested today EasyUEFI Free, and does not mess anything. You can safely use EasyUEFI on Windows and Boot Manager on macOS. They do basically the same thing.
I started to learn some of the basics of the Windows boot handler, Probably I can port Boot Manager and release a Windows version by the end of the year, as an alternative of the BootCamp panel and their not working "Restart on OS X" function.
I started to learn some of the basics of the Windows boot handler, Probably I can port Boot Manager and release a Windows version by the end of the year, as an alternative of the BootCamp panel and their not working "Restart on OS X" function.
A bit off-topic, but does anyone have any recommendations for a NVMe solution for a MacPro5,1? It works to boot MacOS from such a drive with the driver included in Boot Manager?