MP 1,1-5,1 Can I partition my boot NVMe while using Windows 10?

[Dwight__SCHRUTE]

I have a 5,1 cMP. Currently it boots off of an NVMe (10.15) or an SSD (Windows 10). Right now I am using Windows 10 and a GTX1080.

I certain piece of video hardware I am using won't work under Windows and I need 10.13 to run the Nvidia GPU. I need to partition my existing boot drive and install 10.13. Is this possible to do while using Windows?

Also as an aside does anyone know where I can get a copy of 10.13? I have tried the App Store but it refuses to download as it states that I have a newer OS.

Thanks

 

[chscag]

This works for me and I'm running Catalina:

https://apps.apple.com/us/app/macos-high-sierra/id1246284741?ls=1&mt=12

 

[Dwight__SCHRUTE]

This works for me and I'm running Catalina:

https://apps.apple.com/us/app/macos-high-sierra/id1246284741?ls=1&mt=12

Thanks. I've tried that link before. I click on it, a new dialogue box appears saying "finding update" and then I get the following message:

This copy of the “Install macOS” application is too old to be opened on this version of macOS.

 

[chscag]

Hmm, I don't understand why that doesn't work for you. When I go there the button to download High Sierra is labeled "Get" with a down arrow and cloud symbol.

I just tried it again and it allowed me to start the download even though I'm currently running Catalina on my iMac.

 

[startergo]

I have a 5,1 cMP. Currently it boots off of an NVMe (10.15) or an SSD (Windows 10). Right now I am using Windows 10 and a GTX1080.

I certain piece of video hardware I am using won't work under Windows and I need 10.13 to run the Nvidia GPU. I need to partition my existing boot drive and install 10.13. Is this possible to do while using Windows?

Also as an aside does anyone know where I can get a copy of 10.13? I have tried the App Store but it refuses to download as it states that I have a newer OS.

Thanks

In Windows you can use gdisk. Also you can create partition on the NTFS drive in disk management. If you have to modify the APFS partition you need to boot Catalina. You can use https://github.com/corpnewt/gibMacOS to download Apple OS.
Or this:

How do I download macOS High Sierra for offline install?

Yes, I found macOS High Sierra media installer but this don't fit my use-case. I need to update a number of Macs to High Sierra to address Spectre/Meltdown ASAP, and the questions linked above had...

apple.stackexchange.com