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THIS IS A PROVISIONAL GUIDE THAT IS INCOMPLETE, CHANGES ARE BEING MADE CONSTANTLY, USE AT YOUR OWN RISK After about 3-4 days of researching, I'm confident enough to start a provisional guide for 2015 Edition Macbook Pro Retinas both 13" and 15" that have dedicated AMD GPUs instead of nVidia GPU's. A few people have stated that it is impossible to use an eGPU with the new 2015 Macbook's but I believe this is simply not true. After chatting with 2 different Apple engineers at a Genius Bar, I was told that no changes were made to the new 2015 line of Macbook's that would effect the application of a eGPU build, and that it's highly possible to do so. With this in mind I decided to continue with my project and was able to do some extensive research on what parts I would need and what I would need to do with the software. The hardware remains the same, meaning there's nothing extra you should buy, that you would not have bought if you were building an eGPU for any other Macbook. The software, from what I can see is where it gets tricky but I'll get to that later. First off I purchased these: Power Supply - Used to power parts. GPU/Graphics Card - The thing that's going to play Star Wars Battlefront on High Settings at 60 FPS (hopefully) Akitio Case - Used to make GPU thunderbolt Compatible. (You're connecting your thunderbolt cable to this, as GPU's don't have thunderbolt ports). Barrel Plug - Used to attach Dell DA-2 Power supply to Akitio Case and GPU. Super HD Drawing of how the Connections look like Imgur You set up the Hardware like you would any eGPU build. 1. Connect Graphics Card to Akitio Case. 2. Connect barrel plugs 8-pin PCIe end to the Dell DA-2's 8-pin plug. 3. Connect one of the 6 pin PCIe plugs coming from the Barrel into the Graphics Card 4. Connect the Barrel to the Akitio case in order to power the case. 5. You have now powered the GPU and the Akitio case. 6. Your hardware is ready. Now onto the provisional software guide: The software is currently being worked on until my eGPU parts come in to test if it actually works (thus this being a provisional guide) (Requirements: Windows 8.1) At first I thought that the software would be just like any other Apple e-GPU project. Meaning, connect eGPU, install drivers etc. However, the new 2015 line of MBPr's that have dedicated GPU's (dGPU), use AMD rather than nVidia. What this means is that you can no longer use nVidia's Optimus technology in order to connect the eGPU to the new Macbooks with dedicated GPU's. What Optimus does is if it detects that there are 2 nVidia cards connected to the device (the one in the Macbook and the eGPU), it switches to the one with the most power, which would be the eGPU, automatically disabling the default dGPU for you. This allows someone with a 2014 Macbook that has a dedicated GPU, to use the internal LCD screen (the Macbook screen). This is not the case with the new MBPr's with AMD dGPU's. So now, we have to figure out a way to disable the default AMD dGPU and enable the Intel iGPU, which should allow you too use the eGPU for the internal monitor. The problem is that device manager doesn't show the Intel iGPU by default, as that's the way Bootcamp is optimized. It is explained in more detail in the thread below. If you have one of the new 2015 MBPr's with a dGPU and you were to go into device manager on Windows, you would only see the AMD dGPU. You wouldn't see the Intel iGPU. In order to solve this issue I looked at THIS thread. This thread basically solved the whole problem, thanks to users @ah- for providing the file that makes it so device manager shows Intel's iGPU (Intel Iris Pro 5200). The instructions for device manager to show your iGPU are as follows: (Huge thanks to @juniordiscart , wouldn't be able to do this without him) 1. Install reFIND via Windows. 2. Reboot your computer, you should now see a new boot screen. You will see this every time you boot up from now on. Boot back into Windows. 3. Download THIS file and place it on your desktop. 4. Open up Command Prompt, run as administrator. 5. (Thanks to @juniordiscart for the clear and concise instruction) Enter the following commands: mountvol S: /S This will mount the EFI partition in Windows and assign it the drive letter S. You won't be able to see it appear in "My Computer" however, it remains hidden. S: cd EFI dir Check the output after these commands. If you see a directory for refind, then you have refind installed and you can proceed with the next set of commands. Otherwise, make sure you follow the installation instructions for rEFInd for Windows onthis link: The rEFInd Boot Manager: Installing rEFInd xcopy /E C:\Users\YOURUSERNAME\Desktop\apple_set_os.efi S:\EFI\custom\ This last one copies the efi file to the custom folder of the EFI partition. Make sure you get all of the "\" right and that your path to your apple_set_os.efi file is correct. It should ask you to create any custom directory if you don't have one already. 6. Now that you've done the hard part, when you reboot you should be brought to the reFIND boot screen and there should be a new option called something like "apple_set_os.efi". Open this up. 7. It should flash the screen quickly and bring you back to the reFIND boot screen. (If it opens up and stays on the screen for more then a minute, shut off your computer and try again) 8. Boot to Windows. 9. Check device manager. Your Intel iGPU should now show up. Congrats you've done the hard part! Now install your Intel Drivers ( https://downloadcenter.intel.com/ ) BUT WAIT------ While installing your Intel drivers your screen will flash black and most likely freeze up. Let it sit like that for a couple of minutes or so and shut down your computer by holding the power button till it turns off. Turn it back on, and REPEAT STEPS 6-7 above. Every time you shut down your computer you have to first start up the "apple_set" efi file, then start Windows. Or else your iGPU won't show. Now you have the latest Intel drivers. Disable your dGPU in Device Manager (right click it, disable), your Macbook should auto switch to the Intel iGPU. Personally, all of the above worked great for me. I was able to disable the dGPU and use my iGPU. The speed at which the 2880 resolution screen ran was evidence enough that it worked. Now, we wait Since my parts haven't come in yet I'm not able to see if connecting the eGPU will allow me to use the Mac's internal display, but they should be here soon so I'll update as soon as I get them. (To be continued.....) Edit: If anyone can explain to me what error 12 is and how it occurs please do . Thanks!