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Jake Lo

[Deprecated] Changing DVMT values in BIOS

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Steps to change the DVMT value (Done on Windows or WinPE)


/!\ Warning, some files in attachment will show as infected, you'll need to disable your antivirus temporarily

     Use at your own risk!

1) Universal BIOS Backup ToolKit 2.0.exe - to backup the BIOS (i.e. DellInc.-A07.rom)
2) UEFITool.exe to find the module labeled SetupPrep (not Setup as per FireWolf’s guide) and extract the PE32 image section (setup.bin)


  For Dell Only: Search with this GUID, right click the GUID found and select extract body. Save it as setup.bin


3) Universal IFR Extractor.exe to extract setup.bin to a readable text file
4) Use notepad to search for “DVMT” in the text file

    i.e. for the E7450, 2 were found at 0x432 and 0x433 but only 0x432 needs to be changed to 0x3
5) Format an USB drive to fat32 and create a folder name EFI
6) Download the EFI Shell and extract the Boot folder to EFI folder (EFI/Boot/bootx64.efi)
7) Boot system with the USB and select UEFI Boot
    At the grub prompt, enter these commands, hit enter after command, then exit and reboot
    i.e. setup_var 0x432 0x3

To verify if the value was updated, just enter setup_var 0x432 and hit enter, the value will be listed

More detailed instruction in attachment


/!\ Alternatively, just use Lilu.kext + IntelGraphicsDVMTFixup Whatevergreen without having to mess with the BIOS






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Is there an updated guide for this @Jake Lo??


The word doc in the archive seems incomplete.


Also, I get an error when I try using Universal IFR Extractor. Says "Protocol: Unknown" instead of "Protocol:UEFI"


Edit: Ignore me, I realised you can use the kexts instead

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Yes, also the rest of the instruction is in the same post above.

I guess I could've include full instruction in the text file as well.

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I'd honestly go against anything related with patching your BIOS since any small mistake could render you high end latitude laptop useless.Jake Lo's bootpack contains the IntelGraphicsDVMTFixup kext, so in theory, you should be able to install macOS on your laptop without having to patch your BIOS like I did.

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Since WhateverGreen aims to be an ultimate graphic solution which replace all other graphic fixes, those other solutions are now deprecated and integrated in WhateverGreen. That includes IntelGraphicsDVMTFixup too, but do not expect that your DVMT problem would be fixed just by adding WhateverGreen to your Clover kexts folder as it was a case with IntelGraphicsDVMTFixup.


DVMT patch doesn't work "as is" and currently there is no simple switch that you can use. To fix DVMT, you need to set few framebuffer properties in Devices/Properties of your Clover config. Detail info here. Please check details in Preliminary part, since there is a list of things that should be removed if you are using WhateverGreen.


In short, you need to remove all other kexts and graphics injections and fixes in Clover related to graphics and to set framebuffer patches in Devices/Properties like this:


framebuffer-patch-enable01000000 (this is actually 00000001, but it needs to be in reverse order) - enable patch

framebuffer-stolenmem00003001 (this is actually 01300000) - set framebuffer to 19MB

framebuffer-fbmem00009000 (this is actually 00900000) - set cursor to 9MB





Device path of your IGPU -  PciRoot(0x0)/Pci(0x2,0x0) should be added to Devices before setting properties.

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The IO addresses for laptops' GPUs are actually standard across the board; it's not just a Dell thing, it's the same for all computers, including Apple's own MacBooks

iGPU -> @0x00020000
dGPU -> @0x00010000


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Thank you very much @Hervé. That is very useful info. I just followed official instructions since I didn't knew that. I just noticed that in most Dell laptops that path is same. Now is clear why. I updated my previous comment to simplify it. 

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My Dell 5570 has  these values :

Setting: DVMT Pre-Allocated, Variable: 0x795 {05 91 30 05 43 05 39 27 01 00 95 07 14 10 00 FE 00}
0x3EEC0                 Option: 0M, Value: 0x0 {09 07 31 05 00 00 00}
0x3EEC7                 Option: 32M, Value: 0x1 {09 07 32 05 30 00 01}
0x3EECE                 Option: 64M, Value: 0x2 {09 07 33 05 00 00 02}
0x3EED5                 Option: 4M, Value: 0xF0 {09 07 34 05 00 00 F0}
0x3EEDC                 Option: 8M, Value: 0xF1 {09 07 35 05 00 00 F1}
0x3EEE3                 Option: 12M, Value: 0xF2 {09 07 36 05 00 00 F2}
0x3EEEA                 Option: 16M, Value: 0xF3 {09 07 37 05 00 00 F3}
0x3EEF1                 Option: 20M, Value: 0xF4 {09 07 38 05 00 00 F4}
0x3EEF8                 Option: 24M, Value: 0xF5 {09 07 39 05 00 00 F5}
0x3EEFF                 Option: 28M, Value: 0xF6 {09 07 3A 05 00 00 F6}
0x3EF06                 Option: 32M/F7, Value: 0xF7 {09 07 3B 05 00 00 F7}
0x3EF0D                 Option: 36M, Value: 0xF8 {09 07 3C 05 00 00 F8}
0x3EF14                 Option: 40M, Value: 0xF9 {09 07 3D 05 00 00 F9}
0x3EF1B                 Option: 44M, Value: 0xFA {09 07 3E 05 00 00 FA}
0x3EF22                 Option: 48M, Value: 0xFB {09 07 3F 05 00 00 FB}
0x3EF29                 Option: 52M, Value: 0xFC {09 07 40 05 00 00 FC}
0x3EF30                 Option: 56M, Value: 0xFD {09 07 41 05 00 00 FD}
0x3EF37                 Option: 60M, Value: 0xFE {09 07 42 05 00 00 FE}
0x3EF3E  End of Options {29 02}


I changed to 0x2 and got DVMT=64. I would like to set it to 128 but I don't see such value. That means that my laptop can only get up to 64MB?


Also , 

should I change this value to max (default is 256) ?

Setting: DVMT Total Gfx Mem, Variable: 0x796 {05 91 44 05 45 05 F4 04 01 00 96 07 10 10 01 03 00}
0x3EF53             Option: 256M, Value: 0x2 {09 07 47 05 30 00 02}
0x3EF5A             Option: 128M, Value: 0x1 {09 07 46 05 00 00 01}
0x3EF61             Option: MAX, Value: 0x3 {09 07 48 05 00 00 03}
0x3EF68  End of Options {29 02}


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