Legacy NVIDIA Patching

  • Please note this page is more of an info dump, we won't be going to too great of detail on setup though we plan to expand this page more for it.

With legacy NVIDIA GPUs, macOS has difficulties enabling acceleration due to many missing properties. To work around this, we can inject properties into IOService for macOS to easily interpret.

To start off, we'll be assuming the following:

  • macOS has already been installed in some way
    • We need macOS installed to determine certain properties
  • Your GPU is either Fermi or older
    • Kepler and newer do not need Device Property injection
  • Lilu and WhateverGreen are loaded
    • verify by running kextstat | grep -E "Lilu|WhateverGreen"

Finding the GPU pathing

First lets grab gfxutilopen in new window and run the following:

path/to/gfxutil -f display

This should spit out something like the following:

67:00.0 10DE:0A20 /PC02@0/BR2A@0/GFX0@0/ = PciRoot(0x2)/Pci(0x0,0x0)/Pci(0x0,0x0)

What we care about is the PciRoot section, as this is where our GPU is located and where we'll be injecting our properties:


Building our DeviceProperties

With NVIDIA GPUs, there's actually not too many properties required for setup. The main ones that are recommended are the following:

modelex. GeForce GT 220GPU model name, cosmetic
device_typeNVDA,ParentAlways set as NVDA,Parent
VRAM,totalsizeex. 0000004000000000Sets VRAM size
rom-revisionDortaniaProperty must exist, however the value can be anything
NVCAPex. 0500000000000F00000000000000000F00000000sets display properties used by macOS, more info below
@0,compatibleNVDA,NVMacAlways set as NVDA,NVMac
@0,device_typedisplayAlways set as display
@0,nameNVDA,Display-AAlways set as NVDA,Display-A
@1,compatibleNVDA,NVMacAlways set as NVDA,NVMac
@1,device_typedisplayAlways set as display
@1,nameNVDA,Display-BAlways set as NVDA,Display-B

And to calculate the properties few properties:


Technically cosmetic, however macOS expects this entry so we'll provide it. The format is as follows:

GeForce [Device Name]
# Example
GeForce GT 220


Amount of VRAM present on your card, in hexadecimal.

For this example, lets convert 1024MB to hexadecimal:

# Convert 1024MB Megabytes to Bytes
echo '1024 * 1024 * 1024' | bc

# Convert from decimal to hexadecimal
echo 'obase=16; ibase=10; 1073741824' | bc

# Hexswap so it can be injected correctly
# ie. swap in pairs
40000000 -> 40 00 00 00 -> 00 00 00 40

# Pad the value to 8 bytes with 00 at the end
00 00 00 40 00 00 00 00

# And you're done
VRAM,totalsize = 0000004000000000


Simply can be any value, however the property must exist as some GPUs fail to initialize without it(ex. GT 220's)

rom-revision = Dortania


This is where the fun comes it, as we'll now need to calculate the NVCAP value. Thankfully for us, 1Revenger1 has created a tool to automate the process: NVCAP Calculatoropen in new window

To use this program, simply grab your VBIOS(TechPowerUp hosts most VBIOSopen in new window) and run NVCAP-Calculator within your terminal.

Once its running, you should see the following:

Give it your VBIOS and then press enter. Once it takes you to the main menu, select option 2 to take you to the NVCAP calculation page.

Here you can see the connectors that NVCAP-Calculator was able to find. Each Display may represent multiple DCB Entries, such as DVI (normally represented as two entries) or duplicate DCB entries. The goal here is to assign each display to a head. Each head can only output to one display at a time. For example, if your using 2 DVI ports, each should be on their own head to have proper dual monitor support.

Note that some displays may be assigned automatically. An LVDS display will be put on it's own head automatically, and TV displays will be put on the TV head automatically.

To start assigning displays, press 1. To assign a display to a head, you type the number of the display then the number of the head. For example, typing in 1 1 results in:

You can type in 1 1 again to remove the display from the head. Once you are done assigning displays, it should look something like this:

Once you are done setting up the displays, press q to return to the other NVCAP settings. You should set the rest of the NVCAP settings as follows:

NVCAP ValueDetailsExample Command
Version04 for 7 series and older, 05 for 8 series and newer3 then 4
Composite01 for S-Video, 00 otherwise4 to toggle
Script based Power/Backlight00 ony useful for genuine MacBook Pros3 to toggle
Field F (Unknown)0F for 300 series and newer, otherwise 076 then 0x0f

Once done, enter in c to calculate the NVCAP value

You now have your NVCAP value!

05000000 00000300 0c000000 0000000f 00000000

For those who are wanting a break down on how to calculate the NVCAP value:


Info based off of WhateverGreen's NVCAP.bt fileopen in new window

NVCAP BitNameComment
Byte 1NVCAP Version04 for 7 series and older, 05 for 8 series and newer
Byte 2Laptop with Lid01 for true, 00 otherwise
Byte 3Composite01 for S-Video, 00 otherwise
Byte 4Backlight01 for Tesla V1 with Backlight, otherwise 00 for newer GPUs regardless of screen type
Bytes 5+6TVDCBMask00 00, relates to DCB entry 5
Bytes 7+8Head0DCBMask00 00, see below
Bytes 9+10Head1DCBMask00 00, see below
Bytes 11+12Head2DCBMask00 00, non-applicable for Fermi and older
Bytes 13+14Head3DCBMask00 00, non-applicable for Fermi and older
Byte 15ScriptBasedPowerAndBacklight00, only relevant for genuine MacBook Pros
Byte 16Unknown0F for 300 series and newer, otherwise 07
Byte 17EDID00
Byte 18Reserved00
Byte 19Reserved00
Byte 20Reserved00

Cleaning up

Now that we've gotten all our properties, we can now add em up and place them in our config.plist:


model          | String | GeForce GT 220
device_type    | String | NVDA,Parent
VRAM,totalsize |  Data  | 0000004000000000
rom-revision   | String | Dortania
NVCAP          |  Data  | 05000000 00000300 0c000000 0000000f 00000000
@0,compatible  | String | NVDA,NVMac
@0,device_type | String | display
@0,name        | String | NVDA,Display-A
@1,compatible  | String | NVDA,NVMac
@1,device_type | String | display
@1,name        | String | NVDA,Display-B

Open your config.plist and head to DeviceProperties -> Add, next create a new child with the name of your GPU's path(ie the one with gfxutil). Then, finally add the properties as children to the PciRoot. You should end up with something similar: