Dell XPS 13 i7-1065G7 Video Memory Stuck at 35MB after patchig DMVT Monterrey

[banditch_]

EFI:

OC.zip

drive.google.com

Hardware

• Model: Dell XPS 13 7390 2-in-1
• CPU: Intel i7-1065G7 (Ice Lake, Iris Plus G7)
• iGPU: Device-ID 0x8A52
• BIOS: 1.9.1 (InsydeH2O)
• macOS: Monterey
• Bootloader: OpenCore

Problem
No matter what I do, VRAM is stuck at 35MB and the system behaves like it’s only partially accelerated:

• Dock is not transparent
• UI animations stutter badly (Mission Control, app minimization, Safari previews, dictionary popups)
• System freezes for a few seconds during animations
• About This Mac shows ~35MB VRAM
• Clearly not proper Metal acceleration behavior

• System boots and runs
• No kernel panics with the correct framebuffer
• Removing -igfxvesa and fallback args exposes the real issue
• Graphics acceleration appears partial at best
• BIOS does not expose DVMT options
• Used GRUB setup_var to patch DVMT
• Variables confirmed writable (5C0 / 5C1 etc)
• DVMT changes do not affect VRAM reporting in macOS
• Variable 0x785 (mentioned in older XPS guides) exists but reads 0x00
• Unsure if touching 0x785 on Ice Lake / this BIOS is safe or relevant
• iGPU correctly identified as Intel Iris Plus Graphics
• Device-ID shows 8A52
• AAPL,ig-platform-id sometimes shows ffffffff despite injection
• Metal plugin loads, but behavior suggests fallback or incorrect memory layout

Questions i have:

• Why is VRAM hard-capped at 35MB on this Ice Lake system?
• Is there a missing Ice Lake–specific DVMT or memory variable on Dell XPS 7390?
• Is BIOS variable 0x785 relevant for Ice Lake, or is that Skylake/Kaby Lake only?
• Why does the same framebuffer config work on identical hardware but not here?
• Is this a firmware lock, not a macOS config issue?
• Can i get acceleration working???

 

[EliteMacx86]

EFI:

OC.zip

drive.google.com

Hardware

• Model: Dell XPS 13 7390 2-in-1
• CPU: Intel i7-1065G7 (Ice Lake, Iris Plus G7)
• iGPU: Device-ID 0x8A52
• BIOS: 1.9.1 (InsydeH2O)
• macOS: Monterey
• Bootloader: OpenCore

Problem
No matter what I do, VRAM is stuck at 35MB and the system behaves like it’s only partially accelerated:

• Dock is not transparent
• UI animations stutter badly (Mission Control, app minimization, Safari previews, dictionary popups)
• System freezes for a few seconds during animations
• About This Mac shows ~35MB VRAM
• Clearly not proper Metal acceleration behavior

• System boots and runs
• No kernel panics with the correct framebuffer
• Removing -igfxvesa and fallback args exposes the real issue
• Graphics acceleration appears partial at best
• BIOS does not expose DVMT options
• Used GRUB setup_var to patch DVMT
• Variables confirmed writable (5C0 / 5C1 etc)
• DVMT changes do not affect VRAM reporting in macOS
• Variable 0x785 (mentioned in older XPS guides) exists but reads 0x00
• Unsure if touching 0x785 on Ice Lake / this BIOS is safe or relevant
• iGPU correctly identified as Intel Iris Plus Graphics
• Device-ID shows 8A52
• AAPL,ig-platform-id sometimes shows ffffffff despite injection
• Metal plugin loads, but behavior suggests fallback or incorrect memory layout

Questions i have:

• Why is VRAM hard-capped at 35MB on this Ice Lake system?
• Is there a missing Ice Lake–specific DVMT or memory variable on Dell XPS 7390?
• Is BIOS variable 0x785 relevant for Ice Lake, or is that Skylake/Kaby Lake only?
• Why does the same framebuffer config work on identical hardware but not here?
• Is this a firmware lock, not a macOS config issue?
• Can i get acceleration working???

Attach your EFI to check

 

[banditch_]

Attach your EFI to check

its on the google drive link https://drive.google.com/file/d/1krqB2kPyDdsvkhz9JAFADm6BzyUr39iv/view

 

[EliteMacx86]

its on the google drive link https://drive.google.com/file/d/1krqB2kPyDdsvkhz9JAFADm6BzyUr39iv/view

You've set the APPL,ig-platform-id wrong. It should be 0200518A. You'll also need to add -igfxdvmt in boot args.

 

[banditch_]

it hanged then rebooted on screen the last lines where as the image shows, also if it helps just before stalling the screen dims a bit. Thanks so much for the support

here is the updated efi: https://drive.google.com/file/d/1GV0en2Tgi38zAmyroQ7Cc5n3z4CC02VD/view?usp=sharing

 

[EliteMacx86]

it hanged then rebooted on screen the last lines where as the image shows, also if it helps just before stalling the screen dims a bit. Thanks so much for the support

here is the updated efi: https://drive.google.com/file/d/1GV0en2Tgi38zAmyroQ7Cc5n3z4CC02VD/view?usp=sharing

Seems like DVMT issue. Reflash your BIOS and then check the EFI.

 

[banditch_]

i reflashed the bios version was 1.9.1 and still hangs with the same behaivour i dont know what variables are dvmt prealloc and can't change them i tried to use linux to find what variable to find but i couldn't