MP 1,1-5,1 EFI Boot boot of Mac Pro 2008

[ZNDK]

My Mac Pro 2008 always freezes when I click EFI Boot on the bootloader screen. I want to install Windows 10, but I am having trouble booting my Windows media.
When I try to boot with a Windows 10 DVD disc, the boot loader screen shows "Windows" and "EFI Boot" will be displayed. I click on "Windows" and the progression shows only the Windows logo and does not go on. I click on "EFI Boot" and it immediately freezes. Freezing due to EFI Boot occurs regardless of USB memory, HDD, or DVD.

I have tried PRAM Clear. Is there any other solution? I also tried OpenCore, but it doesn't seem to work with MP3.1.

Please help.

 

[joevt]

You can't install Windows using UEFI 2.x on Mac Pro 2008 because Mac Pro 2008 has EFI 1.1 (at least not without some hacks), Therefore you need to use the Windows option.

If the Windows option fails, it may be because of PCIe devices that you have installed. What devices do you have installed? The problem may occur with any PCIe device that has a BIOS option rom (such as some PCIe cards that claim to be bootable for Windows).

I think DVD is the best option for Mac Pro 2008. USB might not work (or it might work only if Windows is not already installed - this behavior might be for other Macs?)

 

[Dayo]

This guide should work for you:

Bare Metal Windows on cMP

PART 1 of 3 This is a guide to installing Windows 10 Bare Metal on Classic MacPros without Bootcamp or similar. This is one of many ways to do this but is a straightforward method. This guide is for installing Legacy Windows as opposed to UEFI Windows but can be used for installing UEFI...

forums.macrumors.com

Best to install Legacy Windows and use something like RefindPlus.

OpenCore needs UEFI Windows which can also be installed using that method but I don't think UEFI Windows can be readily installed on a cMP3,1.

 

[ZNDK]

If the Windows option fails, it may be because of PCIe devices that you have installed. What devices do you have installed? The problem may occur with any PCIe device that has a BIOS option rom (such as some PCIe cards that claim to be bootable for Windows).

I have only added a video card. I have replaced the video card with a RADEON HD6850(Flashed to Mac EFI ROM).
I reverted back to my original nvidia GeForce 8800GT and the situation remained the same.

The EFI Boot of the Windows installation media (USB memory) created by the BootCamp assistant(include El Capitan) freezes in the same way. Is this also EFI 2.x?

 

[ZNDK]

As it turns out, I was able to install Windows itself. I was unable to install using the Mac Pro's internal DVD drive, but was able to successfully install from an external DVD drive (USB). Moreover, I had to go back to Windows 1709 install media. I was not able to use EFI Boot on the bootloader screen, and could only install Windows in MBR mode by selecting "Windows". It took me about 15 minutes to move on from the Windows logo screen.
For some reason, when I insert a DVD with Windows 10 18xx or later when starting up my Mac Pro, it is not recognized and ejected.

Is my Mac faulty and I can't use EFI Boot? Or is it a specification factor?

 

[joevt]

Is my Mac faulty and I can't use EFI Boot? Or is it a specification factor?

MacPro3,1 doesn't have the EFI stuff that Windows wants. No one has created a guide to boot Windows using EFI on MacPro3,1 maybe because it's not possible. Maybe it is possible but some modifications and extra setup are definitely required.

 

[Borowski]

Don't try using (U)EFI for Windows. You don't get any advantages on such old machines and it could brick your firmware, making your mac unusable.

 

[Soba]

Don't try using (U)EFI for Windows. You don't get any advantages on such old machines and it could brick your firmware, making your mac unusable.

@ZNDK This is correct. The classic Mac Pro systems do not support UEFI. Using UEFI mode in Windows 10 can ruin the Mac, forcing you to replace the entire logic board. Use MBR mode for Windows 10. You are already doing this, so you are exactly where you should be.

I don't have a 2008 Mac Pro anymore, but I believe you can run the latest Windows 10 on it and get all the hardware working with drivers available through Boot Camp or Windows Update. If you have trouble updating Windows or installing drivers, let us know and someone will help you with that.