Bootcamp Windows 7 installation woes

[macstatic]

I'm trying to install Windows 7 through Bootcamp but it's not going smoothly to say the least.
I'm on a mid-2010 Mac Pro (cMP 5,1) and I've made a clean install (installed to an empty drive, not an upgrade from an earlier MacOS version) of MacOS 10.13.6 High Sierra.
Actually, I'm starting with a quote from the "Sapphire Radeon HD 5870" thread, where I asked about this and felt it became off-topic, hence a new thread here.

I mean do not install Windows from a USB installer. (macOS is another world, at least macOS won't write a Microsoft digitial cert into a Mac's BootROM. Also, Apple won't create a Mac that cannot understand a digital cert from Apple themselves).

1) Boot from CD -> default to install Windows in legacy mode.

2) Boot from USB flash drive -> default to install Windows in UEFI mode.

It may be virtually no difference to you. But "2" will cause BootROM corruption, which a normal user cannot fix / clear.

OK, I burnt a DVD from the Windows 7 ISO file, and I see it's bootable (from the "Startup disk" system preference), but I didn't quite understand how to install it on the Mac directly from the CD. I suppose for when you want to use a disk on its own, only with Windows on it, right?
However, I didn't think of that at the time as I had already prepared a dedicated hard drive for testing things in my cMP and had MacOS 10.13.6 on it, so instead I ran Boot Camp Assistant and thought I could use the DVD to install it from there.
Well, the creation of a Bootcamp partition went fine, and the DVD was recognized. But when the computer restarted and booted from the DVD in order to install Windows I got into problems....

The problems started here (screenshot above). Obviously I had to choose "Custom (advanced)" which gave me this list of drives:

The alert/warning at the bottom was the same for all my drives (the 52 GB drive is the Windows partition I created in Bootcamp).
Then I remembered from a while back when I was struggling with all this that I had to format the drive once again, so I chose the Bootcamp drive, selected "Format" but got an error message as you can see here. What am I doing wrong?

 

[h9826790]

My suggestion is don't mess up other hard drive, especially don't mix Windows with macOS onto the sam drive. There are plenty of SATA ports on the cMP, just plug in a spare HDD to finish the Windows installation and then flash your card.

 

[Kaspin]

I was doing the same on my MacPro4,1 not long ago. For whatever reason the Bootcamp assistant formats the drive using GPT, but a legacy (CSM) windows installation needs an MBR disk and the installer can't convert it while there are existing partitions on it. Assuming you want to use all of "Disk 1", you should be able to delete all of the partitions, then the windows installer will offer to format the unpartioned space of the disk.

 

[macstatic]

Aha! So you guys are talking about using a complete hard drive/SSD for Windows ONLY, and also WITHOUT using Bootcamp! That sounds like a good idea, because Bootcamp IMHO isn't as easy to set up as Apple makes it out to be.

OK..... after several attempts I've managed to install Windows 7 on a separate hard drive placed inside my cMP

I can now boot into Windows by going to System Preferences-Startup Disk and choose the Windows disk, or (IMHO a better solution if you normally use MacOS, as this will default to boot into MacOS the next time) hold down ALT while the computer starts up, then choose "Windows".
Of course this only works with a Mac-version GPU card or a reflashed PC/Windows GPU card, but I assume you can try it out with something like my old HD-5870 Mac GPU card, take note of the position of the various startup drives, then when you change to the (non-flashed) PC/Windows "Metal" compatible GPU card and have a black screen in front of you after having pressed ALT for a while, you just press the left/right arrow keys the amount of times as you've noted down, then press RETURN to choose it -and after a while it should boot into Windows and the screen should display the Windows desktop where you can reflash the GPU card (so the next time you restart and hold down ALT you will actually see the startup drives on the screen).

I've already taken photos and screenshots of the Windows installation, so if I get the time I want to make a step-by-step guide on how it's done. Might be useful for others as well.

Regarding the BootROM, I'm still concerned and puzzled by this (taken from the "Radeon HD 7950" thread, posting #67):

Don't use USB. It will default to install Windows in UEFI mode, which will write a digital cert into the cMP's BootROM. That can't be removed by NVRAM reset, and effective a kind of BootROM corruption.

If you end up want to use Windows, just burn the ISO to a CD, then hold C to boot (you can do that with your HD7950). And install Windows natively in legacy mode to one of your spare drive. This is good enough for you to flash the card.

Although I followed your instructions and burnt a CD with the Windows ISO image I think I might have tried to install Windows in the past from a USB flash drive (or external USB hard drive) and am worried about having corrupted the bootROM of either my cMP 5,1 or my mid-2012 Mac Pro.
How can I check if this has happened?

I never found any option for selecting either "legacy" or "UEFI" mode when installing Windows 7.
EDIT: After re-reading posting #69 from the "Radeon HD 7950" thread, where it says:

Will, and the 7950 will display even not flashed.


I mean do not install Windows from a USB installer. (macOS is another world, at least macOS won't write a Microsoft digitial cert into a Mac's BootROM. Also, Apple won't create a Mac that cannot understand a digital cert from Apple themselves).

1) Boot from CD -> default to install Windows in legacy mode.

2) Boot from USB flash drive -> default to install Windows in UEFI mode.

It may be virtually no difference to you. But "2" will cause BootROM corruption, which a normal user cannot fix / clear.

.... I think it means that to the end-user (me) I won't see or notice any difference between installing Windows from a USB flash drive or a DVD/CD, but "under the hood" there will be a difference.
Bottom line: I'm not going to install Windows on my Mac from a USB flash drive (I assume the same goes for using a USB external hard drive or USB external SSD drive).

 

[B Bender]

Ive been debating this on my 2010 Mac Pro. I want to Run Pro Tools 10 on Windows 7 so I can use my 32bit plugins. and It wont run on High Sierra. So I either need to do windows on a drive of figure out hot to get Mavericks installed on another drive, and dual boot. I cant find a clean Mavericks dmg anywhere. or I'm doing something wrong with what I had. I messed up and flattened my drive, had to restore, and lost everything so the windows option Hackintosh idea is a possibility, but maybe windows 10?