GTX 980ti eGPU with the 2016 MacBook Pro

December 15th, 2016

I now have a GTX 980 Ti + Razer Core working in both macOS 10.12.2 and Windows 10 on my 2016 MacBook Pro 15" with Pro 460 GPU.

half-on-large half-on-large

Here's what I know:

Windows 10:

Getting it working in Windows was the easiest.

Here's the general overview of what I had to do:

  • Edit my DSDT to add a new large memory block. I followed instructions of others in this thread, and other threads online.
  • Put Windows in Test Mode and applied the DSDT.
  • Restarted the machine
  • Installed the latest Nvidia drivers.

Booting with the eGPU plugged in causes the boot time to increase dramatically.  The eGPU is mostly hot-pluggable. Sometimes, I get a blue screen when I unplug it.

macOS 10.12.2:

This took me some time to get fully working.

A few things are needed:

automate-eGPU script

tb3-enabler

General overview of what I had to do:

  • Patch my IOThunderboltFamily.kext in /System/Library/Extensions using tb3-enabler.
    • This takes the Core from being "Unsupported" in System Information > Thunderbolt to showing as connected.
    • The USB ports on the Core now work after a restart.
    • An Nvidia card shows up in System Information > Graphics/Displays, but no drivers are loaded (haven't installed them yet)
  • Run automate-eGPU.
    • This installs a patched version of the Nvidia web drivers with support for eGPUs.
    • It also fixes a few other common eGPU issues.
  • Add the nv_spanmodepolicy=1 kernel argument to use a 4K or 5K MST display (optional)
    • automate-eGPU adds itself to /usr/local/bin/automate-eGPU.sh and runs on boot to set kernel arguments.
    • Nvidia Web Drivers will not support MST displays unless this argument is passed.
    • Search through automate-eGPU.sh for boot_args and add the nv_spanmodepolicy=1 boot argument everywhere you find nvda_drv=1
    • Restart the machine at least two times.

Notes:

  • Test the eGPU without any screens plugged in. You'll hear the GPU fans die down if drivers engage. This is the first step to getting it working.
  • I've had graphics glitches and slowness when the Intel iGPU is in use. Turn off Automatic Graphics Switching (use the Radeon Pro GPU) to fix this.
  • I don't need to hot-plug the eGPU when the Apple logo to get the eGPU to work. However, at one point I did (not sure how I fixed that). If your eGPU is not working, you may want to leave it unplugged at boot until the Apple logo appears, then immediately plug it in before the progress bar appears.