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Hi guys,

Would someone be able to outline the benefits of the "iGPU (IGD) full disable" patch?
Does this help with CPU temperatures?
Free up CPU processing power?
Or is there another reason?

Cheers
Andrew
 
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Hi guys,

Would someone be able to outline the benefits of the "iGPU (IGD) full disable" patch?
Does this help with CPU temperatures?
Free up CPU processing power?
Or is there another reason?

Cheers
Andrew
It will free some hardware resources: 128MB or 256MB shared ram (don't recall exactly) and a few irq/dma/dmi resources, but I doubt it will have any impact in cpu temp or processing power. The reason I did this patch is to avoid the annoying Windows BSOD when loading Intel Graphics Kernel Mode driver (igdkmd64.sys) after a windows install.
 
Hi m0bil, thank you for your hardwork for this patch.

I want to ask, Does sleep in Imac 2011 with polaris card GPU work after applying this patch?
iMac 12,x iGPU (IGD) Full Disable patch

This firmware patch removes the Integrated Graphics Device (IGD, Bus 0 Device 2 Function 0) from the PCI bus.
The iGPU will not be initialized, will not be seen by OS nor use any hardware resources.

Behavior is the same as selecting "Disable Integrated Graphics" or "Disable onboard video" in other vendors bios.
As a side effect, it fixes the Windows BSOD when loading Intel Graphics Kernel Mode driver (igdkmd64.sys).

Notes:
  • Tested on iMac 12,x with bootrom 87.0.0.0.0. May work on other Mac models and versions. If you try it watch UEFIPatch output for clues.
  • Sleep works after applying patch.
I have started a Github repository to better keep track of firmware patches, this patch is there.
 
I applied the turbo overclock patch with a modified file for 42x (0x2A).


13% gain single-core and 17% in multicore performance on geekbench on my i7-2600 "non k"

System seems to be stable, but for that matter I need more testing time.

ThrottleStop reported PKg Power around 80w during Prime95 4c/8t (96.1w peak).


Before the patch I manage to reach just 65w... Maybe the original 21.5 bios had some sort of cap that forced the processor to downclock. Maybe thats why my results are above expected.


Throttling is an issue. With single/ dual core tasks the system sustains 4.0 to 4.2Ghz speeds, but with 4 cores within a couple of minutes the multiplier goes down... with fans at full blast and room temperature @24 oC the cores reached 85 oC (peak of 91 oC)
How are you hitting 4.0+ with a 2600 “non-k”?
 
It's not possible, non-k bins are fused at factory. Max speed for a non-k 2600 is 4x3800
Im hitting 4.0 Ghz Single core and 3.9 Ghz Multicore with my 2011 with stock 2600s with your EFI firmware mod.

Single core:
Skärmavbild 2025-01-16 kl. 18.46.39.png



Multicore:
Skärmavbild 2025-01-16 kl. 18.50.02.png
 
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I saw some forum posts of people overclocking non-k sandy bridge 4 bins above max turbo after I asked about it here.

I am pretty certain I applied eeprom flash protection fix to my firmware last time I messed with my imac. I want to give the overclocking a try for my non-k 2600.

Which software based flash programmer is easiest to use?

Intel FPT is a struggle to find. I found a few versions on github and tried it out and it said PCH was not supported on my imac. That was just after a fresh install of windows 10 and before bootcamp drivers though.

Flashrom looks like it needs to be compiled in order to run. I am not familiar with either software. Hoping there is something thats easy to use and has a gui.
 
iMac 12,2 & 12,1 UEFI Windows audio ACPI patch (64bit PCIe address space enabler)

This patch modifies firmware ACPI tables to enable 64bit PCIe address space. This fixes the well known UEFI Windows audio driver error, as well as other potential driver issues in UEFI Windows.

To apply use non-NE UEFITool 0.28, load your firmware file and replace "as is" volume with guid 7E374E25-8E01-4FEE-87F2-390C23C606CD with the .ffs file included below.

View attachment 2139378

Since ACPI tables are platform dependent there are .ffs for the iMac 12,2 27'' (tested working) and iMac 12,1 21'' (not yet tested but should work), make sure to use the one intended for your model.
I have also included original DSDT files as well as the modified version.


In case you want to make your own ACPI mods, firmware volume 7E374E25-8E01-4FEE-87F2-390C23C606CD holds a Tiano compressed blob of ACPI tables, stored one after each other with a 4 bytes header prefix on each table. UEFITool can be used to extract and replace individual tables by right clicking in the "Raw section" (each Raw section is a table) inside the compressed section and using "Extract body..." or "Replace body..." options (that will skip or rebuild the required 4 bytes header as well as handle Tiano compression).
The extracted raw data will be the selected ACPI table in AML (ACPI Machine Language) format. You can use MaciASL to convert and edit them.
Hi @m0bil, I have a MacBook Pro 2011 that I wish to implement the 64bit PCIe address space enabler. I have attached the modified DSDT.aml and DSDT.dsl file and attached the original 7E374E25-8E01-4FEE-87F2-390C23C606CD.ffs extracted from the firmware. May I ask how to integrate the DSDT file into the 7E374E25-8E01-4FEE-87F2-390C23C606CD.ffs module? Thank you.
 

Attachments

  • macbookpro2011DSDT.zip
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  • 7E374E25-8E01-4FEE-87F2-390C23C606CD.ffs.zip
    13.4 KB · Views: 12
Hi @m0bil, I have a MacBook Pro 2011 that I wish to implement the 64bit PCIe address space enabler. I have attached the modified DSDT.aml and DSDT.dsl file and attached the original 7E374E25-8E01-4FEE-87F2-390C23C606CD.ffs extracted from the firmware. May I ask how to integrate the DSDT file into the 7E374E25-8E01-4FEE-87F2-390C23C606CD.ffs module? Thank you.
Hi @m0bil, I have found the modded ACPI module from your github. Thanks.

 
edit:
I found the table - it was raw section #9 !!
 
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@m0bil , see attached for my 64bit PCIe firmware file system with MacBook Pro 10,1 (early 2013 Intel HD 4000 and NVIDIA 650M).

Also, I am interested in troubleshooting the Windows delay with Kepler cards (specifically , my NVIDIA 650M).

The following GUID appear relevant to the NVIDIA video bios:

File GUID: 1B033324-B30E-4F65-B35F-EF12EEE91983
File GUID: 26FA5A1D-5C3E-4070-A9B8-80826B1D7CE1

I am able to use the GOP_Updater tool on the extracted raw section (vbios.raw), however, I can not flash the bios region with my new image:

Updating flash chip contents... erase_write: region (00000000..0x7fffff) is writable, erasing range (0x190000..0x7fffff).
Transaction error!
SSFS: SCIP=0, FDONE=1, FCERR=1, AEL=0
SSFC: SCGO=0, ACS=1, SPOP=0, COP=5, DBC=0, SME=0, SCF=1
Running OPCODE 0x20 failed at address 0x190000 (payload length was 0).
spi_write_cmd failed during command execution at address 0x190000

I can write to this region with flashrom using my ACPI image. I have a feeling that when I replace the raw section with, "vbios_updGOP.rom", a checksum(?) or total volume size does align as expected.

Do you have any steps or suggestions for me?

The Windows delay in UEFI mode does not happen until the NVIDIA Graphics driver is installed.
the delay never happens in BIOS mode (the iGPU is hidden in BIOS/legacy boot, too).
(And adding the UEFI image may not make a difference).

I have an external programmer and am not afraid of a brick : ) thank you.

"vbios_updGOP.rom":

NVIDIA Firmware Update Utility (Version 5.735.0)
Copyright (C) 1993-2021, NVIDIA Corporation. All rights reserved.


Sign-On Message : NVIDIA GeForce GT 650M
Build GUID : Blank
IFR Subsystem ID : Blank
Subsystem Vendor ID : 0x106B
Subsystem ID : 0x00F2
Version : 80.07.26.04.02
Image Hash : C33538C477640D365EA905A1AD91094B
Product Name : NVIDIA GeForce GT 650M

Device Name(s) : GeForce GT 650M
Board ID : Blank
Vendor ID : 0x10DE
Device ID : 0x0FD5
Hierarchy ID : Normal Board
Chip SKU : 652
Project : 1307-0000
Build Date : 04/27/12
Modification Date : 04/27/12
UEFI Version : 0x10033 ( x64 )
UEFI Variant ID : 0x0000000000000104 ( GK1xx MXM )
UEFI Signer(s) : Microsoft Corporation UEFI CA 2011
 

Attachments

  • MBP101.zip
    3.9 MB · Views: 8
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