Hey everybody, I have recently bought an eGPU, and I was wondering if I could get some advice on how to actually set-up the device on my internal iMac display running on macOS, without accidentally breaking my entire system in the process.
System specs
- iMac 21.5-Inch (Late 2012)
- 2.7 GHz Quad-Core Intel Core i5
- 8 GB 1600 MHz DDR3
- macOS Catalina 10.15.3
- NVIDIA GeForce GT 640M 512 MB
eGPU hardware
- Razer Core X
- AMD Radeon Sapphire RX 580 (8GB)
- Apple TB3 to TB2 adapter
- Apple 1m TB2 cable
My questions are what is the best software to use for this? Would it be Set-eGPU or Purge-Wrangler? I can't seem to find an iMac (2012) tutorial that uses an AMD RX580 card with the Razer Core X running on an internal display in macOS, is this even possible, or would it have to be boot camped?
Any help/suggestions/advice is welcome as I am struggling to find the correct solution. Thanks.
To do: Create my signature with system and expected eGPU configuration information to give context to my posts. I have no builds.
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@daniel_godhart, If you already have all the hardware listed, read Purge-Wrangler wiki on how to install and use it. This is the most user friendly solution to enable eGPU feature in macOS Catalina for your Thunderbolt 1 2012 iMac.
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From my understanding, nVidia graphics cards do not work with Catalina. High Sierra is your best bet.
I was in a similar position.
First and foremost...back up your system before doing anything crazy. 
I used Time Machine.
Next, you can search Youtube on how to downgrade. The tutorial may say Catalina --> Mojave, but it's only a matter of copying a different line of code on the Apple website when you're making your bootable drive. I followed some Canadian fella. Not flashy, but I found it easy to follow.
Once you've installed High Sierra, reboot and disable SIP (done by restarting with Cmd + R) and then in terminal, typing "csrutil disable" and then restarting.
Now run Purge Wrangler and Set egpu.
Keep in mind, you will need a dummy adapter (most likely).
That should at least get you started. And THEN you can reinstall all of your applications.
Sometimes the hard way is the only way.
Good luck!
2018 Macbook Pro (i7) 16GB RAM.
Razer Core X + nVidia (EVGA) GTX 1080
High Sierra 10.13.6 (17G66)
27in Apple Cinema Display (Mini DisplayPort)
@picodegallo, hello
I probably didn't get this but please correct me if i'm wrong. the OP says that his iMac 2012 specs has
- NVIDIA GeForce GT 640M 512 MB
Which I also have - I currently have the same specs as the OP but I have an akitio node T3 with adapters T3 to T2 and an RX570. I've used both purge-wrangler and set-egpu. both Updated. But problem is that it is still showing me a black screen when I plug in an HDMI TV (in egpu) then will drop frame rates close to 8-10fps on the iMac screen. Rendering it unusable since it's just really really sluggish now.
I really need some help on this one too. I can't seem to solve it. I've had my egpu for a year now but I can't use it.
thank you! hope someone can help.
iMac 27" Late 2012 / AMD Armor RX 570 4GB / Akitio Node TB3 - currently BLACK SCREENS - HELP!