UEFI Motherboard, but Windows 10 installed in Legacy Mode? (Using 2 Drives : SSD and HDD)

[LaurentLaSalle]

I'm a bit lost after reading the guides and watching a lot of tutorials on how to install OS X on my soon to be (I hope) Hackintosh. I hate it when people asks questions that are already answered elsewhere, and I really hope that my specific situation isn't that common. Any help would be greatly appreciated.

I have a UEFI Skylake motherboard with Windows 10 installed in Legacy mode on a SSD (I didn't do this, the shop did this), and I want to install OS X El Capitan on a separate HDD. So basically, I want a dual boot machine, and from what I understand, UniBeast using Clover will give me just that, but it's not clearly mentioned in the Installation Guide.

I'm a longtime Mac User, so I have access to a Mac, and downloading the latest version of El Capitan (which better supports Skylake if I understood correctly) is obviously no hassle.

I'm not sure if I need to convert my Windows installation from Legacy to UEFI (reinstalling Windows is the last thing I want to do), and I'm not sure if the best way to procede would be to choose UEFI or Legacy in UniBeast. Not sure either if I should inject nVidia drivers or not, since it looks like it's only required for old generations nVidia cards.

This is my setup :
ASUS H170 Pro Gaming LGA1151 Motherboard
Intel i7 6700K CPU clocked at 4 GHz
ASUS ROG Strix GeForce GTX 1060 DirectCU III 6 GB

In my previous experience, booting a PC in BIOS to boot a USB drive was a no brainer. Now, on UEFI, the way ASUS is giving me so many options, it's hard to just load "Optimized Defaults" setting (and I really wish there was a way to save my current settings to go back to if anything goes wrong), or to find where are the settings to disable VT-d, CFG-Lock, Secure Boot Mode, IO SerialPort, and so on.

Any ideas? Do I need to reinstall Windows 10 in UEFI mode to make this process easier, or would that be a waste of time?

Once again, thanks in advance to anyone that can help.

 

[P1LGRIM]

Moved to Multi Booting.

http://www.tonymacx86.com/threads/guide-multibooting-uefi-on-separate-drives.198869/

 

[Going Bald]

Please follow the forum rules and put your hardware in your profile and/or create a sig.

So far as UEF/BIOS settings go, Asus UEFI has a "My Favorites" button that allows you to select and set items in the UEFI and save them so you can always get to them easily. See your manual.

For the dual boot, disconnect Win10 SSD, boot the UniBeast USB you create, format the HDD, Install OS X.
Install Clover bootloader in Legacy Mode. This allows you to be able to boot Windows Legacy mode. If you install Clover UEFI, it will not boot the Legacy installed Win10.
Once you have OS X booting from the HDD, you can reconnect the Win10 SSD, boot to UEFI and set the OS X HDD as first in the BBS HDD boot order.

 

[LaurentLaSalle]

That's awesome!

So the keyword here is multibooting. I'll follow your instructions. Am I right in guessing that creating a USB drive with UniBeast in Legacy Mode is essentially telling the tool to install Clover in Legacy Mode?

Thanks a lot!

 

[LaurentLaSalle]

I have successfully boot in Clover, but I can seem to get the El Capitan Installer to run. Loaded Optimized Default Settings. Then VT-d was already disabled, CFG-Lock as well, I've disabled Serial Port (thinking it was IO SerialPort, hope I am not wrong), and enabled XHCI Handoff. My monitor is plugged directly in the motherboard. My USB key is plugged directly on the motherboard in a USB 2.0 port. But if I can get Clover to run, I don't see how the USB port would be a problem.

I also tried to disabled IOAPIC 24-119 Entries, since it was a problem in previous El Capitan versions (but I am using a fresh installer, so I guess this is version 10.11.6).

How long is it suppose to take before the El Capitan Installer launch? I'm getting the feeling that I am so close, but maybe I missed something…

 

[Going Bald]

I have successfully boot in Clover, but I can seem to get the El Capitan Installer to run. Loaded Optimized Default Settings. Then VT-d was already disabled, CFG-Lock as well, I've disabled Serial Port (thinking it was IO SerialPort, hope I am not wrong), and enabled XHCI Handoff. My monitor is plugged directly in the motherboard. My USB key is plugged directly on the motherboard in a USB 2.0 port. But if I can get Clover to run, I don't see how the USB port would be a problem.

I also tried to disabled IOAPIC 24-119 Entries, since it was a problem in previous El Capitan versions (but I am using a fresh installer, so I guess this is version 10.11.6).

How long is it suppose to take before the El Capitan Installer launch? I'm getting the feeling that I am so close, but maybe I missed something…

This is not a multiboot problem - it is an El Captian installation problem. Please post in the EC desktop support forum and come back to here when you have resolved the issue.