The 2014 15-inch MacBook Pro 750M

Full system specifications: https://support.apple.com/kb/SP704

The 2014 15-inch MacBook Pro with the NVIDIA GeForce GT750M can be one of the most troublesome eGPU hosts and plays well in only certain scenarios. This master thread is an encapsulation of all my discoveries regarding this Mac.

As of writing, the latest version of macOS publicly available is Catalina, 10.15.2. The recommended eGPU configuration for this is to use an AMD eGPU with a Thunderbolt 3 enclosure (see Buyer’s Guide), and Apple Thunderbolt 3 to Thunderbolt 2 adapter. You will require purge-wrangler to ensure that the eGPU is set up correctly. If you are intending to use an external monitor connected to the eGPU, then you will also require purge-nvda. The use of purge-nvda causes multiple anomalies, including but not limited to:

• Loss of sleep and brightness controls on the internal display.
• Loss of clamshell mode and deep sleep, which may require force shutdown.
• Loss of video output from the Thunderbolt and HDMI ports of the Mac.
• Loss of discrete GPU, which needs to be deactivated for the external monitor to work over an AMD eGPU.
• Power draw from the discrete GPU, even if inactive.

You may choose to combat these issues by following a build meant for a similar Mac that makes use of more complicated procedures to ensure that the aforementioned issues do not occur on disabling the discrete GPU: https://egpu.io/forums/builds/MacBook-pro-15-retina-mid-2012-razer-core-x-with-rx-580-and-functional-sleeping-waking-up-and-brightness-control/

It is possible to entirely automate and probably simplify the procedure used in the linked build. However, I have not investigated further due to lack of time, incentive, and the Mac itself, as I switched in 2018.

One other option is to compromise on performance by connecting your external monitor directly to your Mac, and avoid having to use purge-nvda and thus avoid those anomalies.

If instead of an AMD GPU, you happen to have a Kepler-class NVIDIA GPU which you would want to use, then you are in luck because you will only need purge-wrangler or automate-eGPU EFI and can get by without any of the complications above.

If you want to use a newer NVIDIA GPU, such as Maxwell or newer, then you must adhere to three important constraints:

• Use macOS High Sierra or older.
• Use a special boot procedure every time you wish to use the eGPU.
• Be subject to some or all of the above complications mentioned above as purge-nvda will be required.

I recommend avoiding this configuration as much as possible. Note that the boot procedure can possibly be avoided if you use a Thunderbolt 2 enclosure instead. This configuration is also basically impossible to use with bootcamp, unless you use a Thunderbolt 2 enclosure.

With Bootcamp, the situation is simple: As long as you are not using a Maxwell or newer NVIDIA GPU, any eGPU will work normally as long as you boot with the eGPU plugged in. All you need to do is install the correct drivers for the eGPU, unless Windows hasn’t already done so within minutes – though you may still want to update them. This Mac does not support hot-plugging thunderbolt devices in Windows. One exception where a Maxwell or newer GPU may work is with a Thunderbolt 2 enclosure such as the Akitio Thunder2.

To conclude, this Mac can be a pain depending on your eGPU. The no-pain setup for this Mac is to use a Kepler GPU such as the NVIDIA GTX 780, which still supported as of Catalina. But those cards may not be powerful enough, in which case, the next best scenario is to use an AMD eGPU. Explore more in the builds table.