Great news, it is super easy to use one of our EFI cards to install El Capitan on your 3,1/4,1/5,1.
Please note that this set of instructions applies SPECIFICALLY to the cards that require Web Driver and have EFI. Cards that don't REQUIRE the web driver can skip all of this, and you can add them later.
If you are currently running another version of OS X, you are golden.
1. Open the terminal and type:
sudo nvram boot-args="nv_disable=1"
2. Run the El Capitan Installer
3. When it is done (may reboot once or twice) download and install the Web Driver from Nvidia (links on our FAQ page about drivers)
4. Here is the important step, you must overwrite the nv_disable boot arg. Just installing the driver doesn't do this. You must open terminal and type:
sudo nvram boot-args="nvda_drv=1"
If you need other boot args like the 5K one, leave a space after the =1 and include them inside the quotes.
You will be prompted for your password, enter it and hit return. If you wish to verify that this worked, type:
And you will see contents of NVRAM, scroll up to see the boot args. It should just have what you entered inside the quotes. If you still see nv_disable=1 in there, you need to do this again until it is gone.
The easy way to know if you didn't do this correctly is if your screen is super laggy, and has a storm of black lines coming from bottom going to top. This is in software mode where the CPU is drawing the screen.
A good tip on the terminal is that if you use the up arrow key you can scroll through recent entries and use them again, or edit them and correct something if you missed a space. Or, if you recently enabled span mode and then do this install, if you scroll up and find the entry that you used before, you can save yourself some nit picketey typing.