iMac 27” 5K + eGPU RX 5700 XT
First thanks for the massive infos you’re all put together on this great community.
I read that 1903 V1 was the best build to start so I installed it on my bootcamp and dis all updates. I also didn’t connect my mac to internet during the installation to be sure that no updates were installed.
Then I didn’t use the bootcamp software who’s installing all the drivers, did it manually through the Device manager, and finally install the drivers from bootcamp drivers. I tested last update April 2020, Jan 2020, and November 2019 cause I read someone with a same configuration got it worked. No luck at all. My dGPU has the drivers installed properly and my RX 5700 XT is well recognized but error 12.
I only have a dGPU in my mac which is the Readon MX395.
I tried to install the drivers with the eGPU or without same result. Except when it’s plugged in Windows won’t start and loop until i disconnect the eGPU. Same problem goes with macOS on Catalina. My mac even shutdown when i connect the eGPU with a fatal message: “Your computer has been restart” and if i don’t disconnect it the boot loop start.
It’s been only one day so i don’t give up now. But i’m about to. I don’t see what to do or where the a solution might start.
Most of the solution I read were only for macbooks. I looked for which PCI to disable on iMac but couldn’t find any answers otherwise I would try it.
Also correct me if i’m wrong but EFI trick is for enable iGPU right? I don’t have any so i didn’t test that hack. Should I ?
Heard 2004 insider update was also a good choice I tried it once with April 2020 drivers with no luck.
The cold plugged doesn’t work for me i guess because of the loop boot. Even when i plugged in after the windows circles spinning.
Please I need your help to at least get me in the right direction.
Thank you All
@dearmooncake, Boot Camp eGPU setup for internal display acceleration is not going to be easy. It's harder on Macs older than 2017 because their firmware don't have "Large Memory". You will likely need to use automate-eGPU EFI boot loader as well as creating an DSDT file. When I was setting up a 2015 21" iMac with RX Vega 56 eGPU, I needed those two pieces to make it work [build link].
Thanks for reaching out. That’s what I thought. I use the EFI automate to boot with the eGPU plugged in, and now Windows boot normally. Still have the godamn error 12.
I tried to install the drivers (Apr 2020 from bootcampdrivers) when no drivers were installed on my dGPU (R9 M395X) and neither on my eGPU (5700 XT) but after reboot turns out that for whatever reasons my R9 was now in code 43 and my 5700XT recognized as Intel HD Graphic 4000. I don’t understand what happened my iMac only have a dGPU.
Then i restored and try to install Adrenaline Apr 2020 with no eGPU plugged in. Good news R9 is back and no code error. I thought maybe let’s try to restart with EFI boot and eGPU plugged in. Error 43 on R9 and 5700 in 43 too.
The best (if I can call it like that) situation is to hot plug my 5700XT. Then I can see R9 working fine with 2020 drivers and my 5700 as error 12.
Also tried to disconnect the PCIe to WiFi broadcast didn’t worked.
I thought with the EFI boot I was close to a solution cause drivers install without crashes when cold plugged eGPU and both cards are supposed to be recognized. But for whatever reasons with the April 2020 a Intel HD 4000 pops up from nowhere. Do you think that drivers may be the issues and that if i try all the drivers possible maybe one will solved the error 12? Or is it strictly a technical issue which has nothing to do with drivers? Is it possible to identified the issue?
Going back to 1809 would solve the problem or sticking to 1903 is the best choice ?
Thanks in advance I know you may not have the answers but worth to try
I was only able to use the AMD eGPU (in my case it was Vega FE/LC) with iMacs with dGPU (I tried both 2015 and 2017, 27 inch) if I disabled the dGPU in the device manager.
When you do this, you lose acceleration and 5K on your internal display.
But any external displays connected to the eGPU will work.
Only way I was able to get both dGPU and eGPU running well was to use nVidia card (in my case 2080 ti).
@jyin, Thank you for your feedback really appreciate it.
Can i ask u few questions?
How was the performance affected?
And how did you manage to make your eGPU being your only gpu, by that I mean disable the dGPU without having a total crash of the computer ?
Thanks for your help
The Vega is on my wife’s iMac 27’ 2017 now. She wanted to use it on both Mac and Windows.
She plays Civilization 6 on Mac, and Borderlands 3 on Windows with 4K / 60Hz external monitor. We just started playing Halo MCC as well. She is not very FPS conscious, but she is happy enough that she turned down my offer to get her the 5700XT.
She simply hit ‘Disable this device’ in the Device Manager. We didn’t try this w/o external monitor.
She is still on Win 10 1903.259. We turned off the auto-update, so she stay on that version till MS gets their act together.
Thank a lot it’s very helpful 🥳
I guess i should give it a try with a external monitor cause I quit understood that using the internal display is a lots cause or at least too much trouble to get it to work.
Anyway thank you for your help again