[EFI Loader] Error 12 Fix in Boot Camp for Apple T2 Security Chip Macs (apple_se...
Clear all

[EFI Loader] Error 12 Fix in Boot Camp for Apple T2 Security Chip Macs (apple_set_os loader v0.5)  

 of  17

Trusted Member
Joined: 4 years ago
Posted by: @susurs

If you disconnect the eGPU with modified bootx64 in EFI partition - Can it boot normally and use just iGPU without replacing the original file?

Posted by: @itsage

@susurs, The modified bootx64.efi would always load up first. If there's no eGPU detected the EFI loader would start Windows with only iGPU. You can also hit the SKIP shortcut key [z] from what I recall.

And of course if you only use the eGPU occasionally and don't want to be bothered waiting for the EFI loader or hitting Z when booting all the time, you could just install apple_set_os on a flash drive. Then just plug the drive in and hold option when you plan to boot with it, otherwise leave it unplugged and boot normally.

2018 Mac Mini [8th,4C,B] + RX 580 @ 16Gbps-TB2 (AKiTiO Thunder2) + macOS 10.14.6 & Win10 1903 // Win10 on external SSD [build link]

2014 13" MacBook Pro [4th,2C,U] + RX 580 @ 16Gbps-TB2 (AKiTiO Thunder2) + macOS 10.13.6 & Win10 1903 [build link]  

itsage liked
Francesco Ripa
Active Member
Joined: 2 months ago

Thank you a hundred times, now Mac and Windows boot the same way, with the same noise from the GPU’s fans.

System: 2019 MacBook Air, macOS Catalina, RX570

The first time you have to reboot in order to use the eGPU, but you get the notification so it’s all perfect.

Notice: I don’t have bootcamp drivers installed but eGPU just works. Also I’m booting Windows from and external flash drive.

Thanks again!

This post was modified 2 weeks ago

2019 MacBook Air (MacBookAir8,2, 1,6 GHz, 8 GB) + RX 570 @ R43SG-TB3 + macOS 10.15.7 & Win10 on EXT Kingston Kyson USB 3.2 Gen 1 Flash drive (200 MB/s read, 60 MB/s write)

itsage liked
Sam Breen
New Member
Joined: 6 days ago

Apologises if this is posted elsewhere.

I have a 2020 MBP with  a Radeon Pro 5500M. I use the laptop for 99% windows, I need MacOS for a tiny portion of my job, but I prefer windows.

I was hoping to use the resources provided here to boot my laptop into windows on the iGPU, and maybe get some battery battery life. 

I tired a guide and made a bootable USB, which loaded didnt follow through as it could not detect an eGPU.

Any advice would be greatly appreciated.

To do: Create my signature with system and expected eGPU configuration information to give context to my posts. I have no builds.


Active Member
Joined: 6 days ago

thank you so much!! With this I was able to get my configuration going to signature. As of today, in 2021, is there no other way to get an EGPU going? at the moment i'm on windows fast ring channel and i have to change port to the card at every boot, i don't know if it's a very stable solution

2019 16" MacBook Pro [9th,8C,H] + RX 6900 XT @ 32Gbps-TB3 (Razer Core X) + Win10 [build link]  

 of  17