2012 imac 21" [gt640m, i5, TB1] + rx-480 & razr core x Windows boot issue with eGPU
Hi guys, im having a little trouble and hoping you guys may be able to help. I've searched through the forums but I cant find many answers to my exact issues.
In mac OS i have got the egpu working using purge-Wrangler to my internal display however i just get a blank black screen on my external monitor (OS recognises the monitor plugged in but just no display). any ideas?
More importantly im trying to get the egpu working in Bootcamp with little success. I installed windows version windows 10 20H2 19042.610, and downloaded drivers for the rx 480. Windows boots fine, recognises egpu, but I cant select it to be used for high performance tasks (such as games or anything really). Therefore I cant make use of it.
After reading through many forum posts, I tried using ddu to remove dgpu and then booting to install drivers for rx480 but once drivers are removed from gt640m windows wont boot with egpu plugged in. All I get is a white screen which seems frozen so i have to turn off the mac and disconnect the egpu. Windows will successfully boot back in once egpu is disconnected and Windows shows drivers did successfully uninstall but i cant install new drivers without the eGPU plugged in and my iMac doesnt let me hot-plug the egpu.
Any ideas of what im doing wrong?
Thanks for any help if you can
@deezer, I would recommend using automate-eGPU EFI. You may need a DSDT override as well to allocate Large Memory for the RX 480 in Windows. I did a build using 2015 21-in iMac with + RX Vega 56 eGPU [build link]. You can take a look over the setup procedure.
@itsage, Ok thanks. I've read through and been following along with your build minus the DSDT (as i figure i can do that after if i have memory issues yes?) and have got the automate-eGPU EFI setup on a external usb (couldn't set it up on internal drive) but when i go to boot into the EFI loader, press Q and select windows the mac freezes on that screen and i have to reset. it seems to boot into mac OS from it just fine though. any ideas?
Cheers again for your help
-Just an update.
-the eGPU is working in mojave 10.14.6 using either automate eGPU EFI or purge wrangler but only on the internal display. the external display is still recognised but all i get is a blank black screen still.
-for windows, I still can't use the EFI loader as described before. I have got the egpu to work on 20h2 version of windows after installing the rx480 drivers then using ddu on the dGPU, but i can only use external display as the internal display just stays white. (better than no egpu though)