[Solved] [SCRIPT] PurgeWrangler: AMD + NVIDIA eGPUs for all Thunderbolt Macs  

@jeroen-van-keulen Please see the main post's Step 2, which now uses a version-agnostic terminal command. This means you won't have to update the installer every time per version. It will simply fetch and download the latest version automatically.

Hi All,

So first I want to say thanks! These scripts are fantastic. I have a 2015 MacBook Pro, and I've been looking forward to the prospect of have an eGPU. Then I heard Apple dropped support for everything without Thunderbolt 3, which prompted me to find this website. I haven't purchased any hardware yet (because the crypto-mining buttholes screwed up the GPU market), but I was curious how the script worked.

After browsing the purge-wrangle.sh script, I found out it's literally just a string replacement. <Moderated //@mac_editor>. So at this point I understood WHAT worked, but I didn't know WHY it worked.

So I downloaded the Hopper Disassembler, as it is able to show cool things like control flow graphs and convert assembly into pseudocode, which looks like a strange mix of assembly and C. 

BTW, I don't have much experience reverse engineering and modifying executable code, but I do sometimes browse assembly generated from my C++ compiler. 

Here is the pseudocode:

[Please login to see this]

Here is the assembly:

[Please login to see this]

And now we see why only Thunderbolt3 works. <Moderated //@mac_editor>. The purge-wrangler.sh script modifies the kernel extension to only check for the Thunderbolt version that is on your current system.

So basically, I wouldn't say Apple is actively blocking Thunderbolt 1/2. They are just not supporting it. If we had the source code, we could easily change this to support TB2 and TB1.  Oh well. Poop.

@duhlong Posting Apple code (especially disassembled) and discussing the details in public is not recommended/permitted - although we don't have such rules at the moment. I have read your post and you're exactly correct in how purge-wrangler works, but in this case, I feel I cannot approve your post here. Sincerest apologies.

Also, about "actively blocking" vs. "not supported" - I felt the former was more accurate because TB1 & 2 were never supported to begin with. Now they are blocked, in a rudimentary sense.

Edit: Have moderated your post and approved. Good work looking into this. I used Hopper as well.

@mac_editor  Ah, OK. Apologies. I just thought it would be interesting. I didn't consider any legal issues surrounding posting Apple's assembly. That thought did not cross my mind. Though I see you took out a verbal description as well. Also unsure of the legalities of verbally describing such details.

@duhlong Appreciate your understanding! Thank you, and welcome to egpu.io.

Thanks Guys! Works now "almost" like charm. The 580 is detected and also in use. 
Why only "almost"? I have huge problems with sleep/wakeup processes. It seems that my macbook goes not into sleepmode properly and is rebooting. 

Anyone also with the same issues and maybe a solution?

@thefurious Script also has a hibernation disable option. Please try that.

@mac_editor 

THX will try that. 

But what if want to keep the Hibernation Mode?

@mac_editor,

Its fixed and updated. I cant respond to our private message. Somehow this webforum is breaking down on me. I cant quote people anymore, I cant upload anything and my earlier uploads I cant see. And now the latest responses are hovering over the send button in private messages mode, but only in our conversation...

@thefurious Even officially supported configs have sleep issues lol. See here.

@jeroen-van-keulen Thanks for letting me know. Noticed that too. Messages is broken. Doesn't handle long lines well.