Updating to OS X 10 11 El Capitan with a flashed Nvidia GPU in a Mac Pro

Updating to OS X 10.11 with Flashed Nvidia GPUs in a Mac Pro: Detailed update instructions

How to get around OS X 10.11 update issues with flashed Nvidia Mac EFI graphics cards

As reported yesterday, there are some issues with updating to OS X 10.11 El Capitan whilst using an Nvidia GPU with a flashed Mac EFI and the Nvidia Web Driver. This guide will help people with such graphics cards perform the update pain free.
No matter your current version of OS X (unless it is 10.11), follow these steps:

  1. Open the Terminal application and type the following:
    • sudo nvram boot-args=”nv_disable=1″
  2. Download the El Capitan Installer from the App Store
  3. Run the El Capitan Installer
  4. Wait for your system to boot and then download and install the latest Nvidia Web Driver (you can find it here: 10.11 Web Driver)
  5. Again, open the Terminal application and this time type the following:
    • sudo nvram boot-args=”nvda_drv=1″

For every system we have tested so far this process has worked perfectly, if you have any issues just pop us an email at [email protected].
If you have already tried to update and found that you can no longer boot in your system then there are a couple of ways around this. If you have an official Apple GPU lying around somewhere, then remove the flashed card and replace it with this, you should then be able to boot and update the drivers accordingly. If you don’t, you could put your system HDD/SSD into a USB caddy and do the updates via USB through a MacBook/iMac/MacMini.