Hi everyone. I bought my eGPU 3 day before. I have read a lot of implements and tried many times to setup, but they didn't work. I really want to make it work on my laptop since they already cost me nearly 1,000 dollars. Here are the details of my setup: Laptop: [h=1]1. 15-inch MacBook Pro with Retina display[/h]2. CPU: 2.8GHz Quad-core Intel Core i7, Turbo Boost up to 4.0GHz (I think it is i7 4970HQ) 3. GPU: iris 5200 Pro and Nvidia GT750M eGPU Setup: 1. Asus STRIX GTX970 2. Corsair RM 550 3. Sonnet Echo Express SEL 4. 8x to 16x riser 5. Thunderbolt cable Systems: OSX Yosemite and Win 8.1 Process: At first, I want to make the eGPU works on the Yosemite, so I carefully follow the tutorial of Mark. However, after tried many times, the eGPU never worked. Then I changed my system to Win 8.1, which is install in EFI. After followed the instruction about add eGPU on Win8.1 (which is kind of as easy as plug and play), my laptop never boot with the eGPU. Finally, I realize maybe the problem is that I always want to use the internal retina LCD to be the display. Maybe I should try external display. Then I connect my eGPU with a Samsung TV with an HDMI cord and redo all the steps for either OSX or Win 8.1. There was still no magic thing happened to my Asus GTX970. I was really disappointed. Besides, I also tried the Optimus setup tutorial by Evo, the whole thing still didn't work. Since I cannot get all my money back by reselling these stuff and have already spent such a long time on making them work. I really need you guys help and solve the problem. PLEASE HELP ME! THANKS!!!