I had Catalina 10.15.6 installed and used the modified bootx64.efi file to enable the iGPU to get my eGPU to work in bootcamp. I followed this guide here:
egpu.io
The guide was more or less pretty perfect and I was able to get my eGPU to work after doing the thunderbolt 3 port dance trick at startup each time.
But then I installed Big Sur Beta 6 and upgraded to 8 and my bootcamp now results in error code 12 for my AMD 5700 XT card. It refuses to find resources no matter what process I use to DDU the drivers and use bootcampdrivers latest or older drivers. I am running v2004 of Windows 10 and even after completely erasing my Macs and following the tutorial again with a fresh copy of Catalina (10.15.7 this time due to internet recovery), I am STILL unable to get my eGPU to work in windows/bootcamp. I hear similar problems happened with bootcamp when Catalina was rolling out - but I didn't know I couldn't go back after a fresh wipe of the computer and still not get it to work... this is saddening.
2019 16" MacBook Pro (RP5500M) [9th,8C,H] + RX 5700 XT @ 32G...
System specs 2019 16" MacBook Pro w/ i9-9880HK, 32GB RAM, 5500M 8GB, 1TB SSD dGPU: RP5500M 4 GB iGPU: Intel UHD Graphics 630 macOS Catalin...
egpu.io
The guide was more or less pretty perfect and I was able to get my eGPU to work after doing the thunderbolt 3 port dance trick at startup each time.
But then I installed Big Sur Beta 6 and upgraded to 8 and my bootcamp now results in error code 12 for my AMD 5700 XT card. It refuses to find resources no matter what process I use to DDU the drivers and use bootcampdrivers latest or older drivers. I am running v2004 of Windows 10 and even after completely erasing my Macs and following the tutorial again with a fresh copy of Catalina (10.15.7 this time due to internet recovery), I am STILL unable to get my eGPU to work in windows/bootcamp. I hear similar problems happened with bootcamp when Catalina was rolling out - but I didn't know I couldn't go back after a fresh wipe of the computer and still not get it to work... this is saddening.